I'm usually tempted to quit reading when I find errors, but I generally plod on.
I just found a nice NY Times blog entry on the subject. Watch those mistakes.
(I found most of the typos in my three non-fiction books before they were published, but I'm always afraid I'll find more.)
More EDITOR@WORK blog entries
Blog entries from The Auto Racing Journal
(a book of great stories about the Intimidator)
(the book of great NASCAR stories)
More blog entries by Tom Gillispie
Anecdotes by Tom Gillispie