For fun, here are a few errors I happened to notice while reading various books for pleasure, or using for reference.

Dmitry Glukhovsky Metro 2033  Orionbooks paperback, 2010 
p318: "His pursuers didn't immediately break cover, concerned that the monster may return..."		
Mark Hodder The Strange Affair of Spring-Heeled Jack  Snowbooks paperback, 2010 
p217: "... all have been attacked recently, it seems, accept Connie Fairweather..."
p305: "Laying a little beyond the village...the estate was..."
p319: "How far would we wonder from the course we have steered..."
p381: "Oxford leaned against the wall and listed."	
Sir Ernest Gowers, revised by Rebecca Gowers  Plain Words 
Particular Books (Penguin), hardback, 2014
p100:  "... could always bereplaced by a single preposition" 
Drew Magary  The End Specialist 
Harper Voyager paperback, 2011
p93:  "... wearing a white suit and drinking a purple drank out of the very same grail."
p280:  "... and they stop bearing those stupid fang implants..." 
Adam Blade  Book 26: Hawkite - Arrow of the Air
Orchard Books, paperback, 2009 
p95: "om braced his feet..." (Should be Tom)
Last line of last page of book reads:
"No one can conquer him. Leave" 
J.K.Rowling  Harry Potter and the Chamber of Secrets
Bloomsbury hardback, 1998
p29: "The teapot went beserk..."
p34: "Mrs Weasley had appeard..."
p47: "...small, goblin-driven carts that sped along minature train-tracks..."
p89: 'I don' blame yeh for tryin' ter curse him, Ron, ' said Hagrid...
p144: "... like a large and malevolant bat."
p153: "...Harry could saw a gleaming oak door ahead..."
p180: "...seemed to have turned into a miniscule television screen."
p198: "...couldn't supress a thin-lipped smile." 
J.K.Rowling  Harry Potter and the Philosopher's Stone
Bloomsbury paperback, 1997
p83: "We will be reaching Hogwarts in five minutes time."
p140: "... and was now racing long the row behind him;" 
T.H.White The Sword in the Stone
Collins Fontana paperback 1963
p8: "Sir Gumore said..." [Should be Sir Grummore]
p12: "Kay, who was too years older..."
p14: "On the bench their was a jumble of..."
p28: " of those beastly femets..." [Should be fewmets]
p28: "What was that?" eclaimed the Wart.
p52: "That will come to be seen as an insanitary habit," said Merlyn, "though I can't see myself."
p72: "She will use my blood for making patterns with no Walpurgis night."
p82: "It rushed upon the man before it with another piercing scread."
p88: "The trouble with the English Artistocracy..."
p92: "Hail," said King Pellinore.
     "Hail said the Wart involuntarily.
p102: "... only to stalk off in opposite directions with infinitive precaution..."
p116: "... must choose before confessting himself a human..."
p123: "... getting cross and shewing sings of slapping him."
p170: "Does the T. Stand for anything?"
p200: "... which fell upon the company and Saw Master Twyti..."
p218: "... he took the furry atomy without protest..."	 
p219: "The wart did as he was told..." [Should be Wart]
p235: "The walked invisible across the sward..."
p236: "It's dragon's, not giants, that grow really big."
p236: "If a human was to grow to six feet, he would simply snap his bones..."
275: "...lest the traveller should be slain by hidden theives." 
Dean Classics Robin Hood and his Merrie Men
Reed International Books, 1992 hardback				
p8: "Then he carried home its [a boar's] grizzly head..."	
Tess Gerritsen The Silent Girl
Transworld, Bantam paperback edition 2011				
p343: "I say we just let the think take him out."
p396: "Jane's hand was humming with excitement..." 
Brandon Sanderson The Way of Kings, Part 2
Gollancz paperback edition 2010
p168: "The highprinces had tried veryhard to..."
p209: "... glowed softly and gave offa comfortable heat."
p221: "Or youcould be wrong." 
Brandon Sanderson The Way of Kings, Part 1
Gollancz paperback edition 2010
p475: "...making Shinovar one of the only places in all of Roshar where highstorms did not reign." 				
p490: "...for it was one of the only times when the gods did not watch men."	
China Meiville The City & the City
Macmillan Pan paperback edition 2010
p316: "...but the man could not forebear looking at us..."
Tolkien's The Hobbit
HarperCollins 2006 paperback edition
Last page of the story (p351) has the header CHAPTER TITLE instead of THE LAST STAGE
Butcher's Copy-editing
Cambridge University Press, fourth edition
p46: "watch out particularly for alternative spellings, such as judgement/judgement"
The Passage by Justin Cronin
Orionbooks, 2010 hardback edition
p84:  "Richard had been with the project..."  (The character is called throughout by his surname Richards.)
p237: "... he tipped his face forward and wretched into the snow."
p244: "He wretched long after the only thing left to come up..."
p631: "... in the tumble of bodies he heard Michael wretch."
Hyperion by Dan Simmons
Gollancz 2005 paperback edition
(The Consul is a key character who turns out to be a double-agent.)
p305: "The Consult swept the glass left."
p465: "...cried the poet. 'He's a fucking sky.'"
Olympos by Dan Simmons
Gollancz 2006 paperback edition 
p5:  "The street below Helen's apartments...are suddenly filled with running men..."
p296:  "Despite requests from Peaen, Loes, Petyr and Isis - all of whom knew she is pregnant - she stayed outside..."
p406:  "LordGodZeusOrdersAreThatNoMortalShallEve
p451:  "Legend and myth said that Nyx...had given birth do Eris..."
p823:  "Shall wesgo watch John enjoy story hour?"
The Kindness of Women by J.G.Ballard
Flamingo (HarperCollins) 1994 paperback edition
p135:	"Henry was more interested in the remnants of the mid-wife's equipment, the foil caps, spare swabs and mouthpiece.  Miriam sat up and hugged them tightly."
Copy-editing by Barbara Horn
Horn Editorial Books and The Publishing Training Centre, 2008 paperback
pii:	Other Titles by Barbara Horn
Copy-editing by Distance Leaning
p56:  "...from cause to effect, from premiss to conclusion..."
p103:  "Copyright is the legal right to control the use of original intellectual property, and is one of the intellectual property righta."
The Greedy Rabbit and other stories by Enid Blyton
Award Publications 1991 Hardback edition
p113:  "What is the matter?" he said, in his deep voice.
The everyone told him about the bun in the paper bag.
New Hart's Rules: the handbook of style for writers and editors 
Oxford University Press 2005
p55:  "When a title or heading is given initial capitals, a decision needs to bemade..."
You're Next by Gregg Hurwitz
Sphere paperback edition, 2011
p7:  "... one of the only things he remembered about her."
The Snowman by Jo Nesbo
Vintage paperback 2010
p314:  "And wishing he had lost Camilla to a murderer than in this way."
The Redbreast by Jo Nesbo
Vintage paperback 2006
p133:  "Edvard grabbed hold of Dale's gun barrel and stood his face."
Changes by Jim Butcher
Orbit Books 2011, paperback edition
p290:"I am also one of the only people alive who knows how to..."
Thomas & friends: Jack based on stories by Rev.W.Awdry
Egmont edition 2008
"Thomas saw the Flagman and the Driver applied the brakes but they couldn't stop in time."
The Devil's Star by Jo Nesbo
Vintage paperback 2005
p231: "...not asking you to begin liking me over night."
Tell No One by Harlan Coben
unknown edition (page missing) 
p2:  "Lake Charmaine had been the sight of a rich-kids summer camp."
The Hercules Text by Jack McDevitt
Sphere paperback 1986
p228: "The sort of instructions my DNA shoud put out..."
The Lion, the Witch and the Wardrobe by CS Lewis
Hardback, The Folio Society, 1996
p70: "...The potatoes are on boiling and the kettle's singing..."
[and then on same page one paragraph later]
"Meanwhile the girls were helping Mrs Beaver to fill the kettle..."
The Hypnotist by Lars Kepler
Blue Door paperback, 2011
p495: "By the time the helicopter arrived at the hospital in Umea, the bullet had gone straight through Erik's left shoulder muscle..."
The Magician's Nephew by CS Lewis
Hardback, The Folio Society, 1996
'Yes, it is,' said Polly.
'But we've got to get back.' She stood up and...
p155: 'And my wings are beginning to ache,' said Fledge. There's no sign of the valley with a lake in it, like what Aslan said...
The Great Hunt (Book Two of the Wheel of Time) by Robert Jordan
Orbit Books paperback, 1992
p219: 'The vood came slowly, hesitantly.'
(Rand is summoning 'the void'.)
The Shadow Rising (Book Four of The Wheel of Time) by Robert Jordan
Orbit Books paperback, 1993
p658: "Rand must think I'm crazy... Berelain isn't my mother after all." Nynaeve gave her the oddest look. I am a little dizzy for some reason. A nice boy with sweet brown eyes offered to help me upstairs.
Lord of Chaos (Book Six of The Wheel of Time) by Robert Jordan
Orbit Books paperback, 1997
p115:  "Light, but he was growing callused enough..." [should be 'callous']
p242:  "Pausing in the leather-lunged flaying of an abashed young man..."  [presumably should be 'leather-tongued']
Winter's Heart (Book Nine of the Wheel of Time) by Robert Jordan
Orbit Books paperback, 2001
p583: "... my fine Aes Sedaiuloving Tairen friend."
(should be 'Sedai-loving')
Prince Caspian by CS Lewis
Hardback, The Folio Society, 1996
p168: "Miraz would never be so hair-brained as to throw away..."
Beyond the Shadows by Brent Weeks
Orbit paperback, 2008
p279: "As the sheered bars came away..."
The Voyage of the Dawn Treader by CS Lewis
Hardback, The Folio Society, 1996
p14: Some kids who played games about Narnia
Got gradually balmier and balmier..."
p127: "Instantly, a whole chorus of other voice replied..."
p136: "If we had any assurance of saving her by battle, our duty would be very plain. It appears to me that we have none."
[looks as if a zealous editor has changed 'choice' into 'duty'.]
Quantum Thief by Hannu Rajaniemi
Orionbooks paperback, 2010
p270: "You already did you worst."
The Left Hand of God by Paul Hoffman
Penguin Books paperback, 2010
p196: "Delay that!" shouted the sergeant. "Next one who moves..."
[no doubt 'delay' should read 'belay']
The Name of the Wind by Patrick Rothfuss
Gollancz paperback, 2008 
p223: "You're still going?" She asked.
p491:  Perhaps even moreso.
p538:  The unrestricted view in all directions was breath-taking. My only regret is that the clouds had blown in...
[should be 'was', not 'is']
The Wise Man's Fear by Patrick Rothfuss
Gollancz paperback, 2011
p401: "Do come back tomorrow." he smirked a bit.
BBC website 23/6/12:
Faced with the prospect of imprisonment, and perhaps with it the loss of the mathematics post he held at Manchester University, which gave him access to one of the world's only computers...