I'm not an author, but, if it were me, I'd want to know about any & all typos so I get get them corrected, if possible, in any subsequent editions. Maybe you could just say: loved the book, but did you notice typos x, y, & z?

The proper thing to do is to write a letter saying how much you have enjoyed reading the book. (Resist the temptation to engage in a long critical discussion; keep it short and appreciative.) Then, if you wish, you can append a list of typos, with a casual remark like "as I was reading, I jotted down a few misprints which you may want to correct in any future edition". This is a compliment on two levels -- (a) you gave the book your full and careful attention, (b) you think it deserves to be reprinted -- and any sensible author will recognise it as a compliment. But don't treat it as a big deal, and don't, for goodness sake, 'commiserate .. over the lack of thoroughness on the part of the publisher'; that would be very rude. If your friend grumbles to you about the publisher's carelessness, then by all means commiserate; but otherwise it is polite to assume that author and publisher are on good terms with each other.

I don't believe there is any author who isn't gratified to receive appreciative fan-mail. (What authors dread most is lack of response: you pour your critical energies into writing the book, you deliver your manuscript to the publisher with a great sense of achievement, you wait with anticipation for it to appear in the bookshops, and then .. silence ..) Your friend will be touched that you have taken the trouble to write a letter. However, it is polite to say something like "please don't trouble to reply to this note; I just wanted to write to say how much I enjoyed" etc. This shows that you are not the vulgar sort of autograph-hunter who wants a letter from the author as a souvenir, and also conveys the polite implication that the author must receive lots of fan-mail and is probably too busy to reply to all of it.

If you want to show that you have read the book point out some plot points or characters or something that you really enjoyed about the book - discuss until your heart is content.

Then mention the errors.

Overall, yes, if they've got a cooperative publisher, it is good for an author to take note of any typos, broken text, or other errors in the text, since a good publisher will keep all that stuff on file. If there's ever a chance to do another run--either as a reprint because it's been selling well, or as a paperback, or for a foreign English-language edition--they'll take the opportunity to fix them. (A paperback or a foreign edition will almost certainly be published by a different company, since publishers tend to sell off those rights, but any good outfit will clean up any problems they know of.)

That being said, though, I really don't think that pointing out typos is the best way to show you've read someone's book. Not only can it come off as a bit passive-aggressive (remember that authors generally have the chance to proof their own books in galley form, before final printing, so anything you catch, they've missed), but it's hardly the most flattering way to make the point. ("How'd you like my book?" "Oh, it was nice! There's a typo on page 79, and I think you misspelled joie de vivre.")

If you want to show your support, make a point of what you found especially convincing or compelling about the book, and open the door to a meaningful conversation. If they engage in a discussion, you'll be able to demonstrate your familiarity with the book clearly. If they don't, you'll know that they're probably a little sick and tired of the topic, and need a break, but will still know that you cared enough to read it.

At that point, you can either bring up the typos with your friend, or just send them directly to the publisher. Especially if you indicate that you know the author, and frame your comments helpfully, most publishers will gladly file the notes.

You can always send the corrections to the publisher, which will get it fixed in a subsequent edition (good!) without necessarily annoying your friend (also good!).

It's good of you to ask. I haven't and wouldn't, unless your friend grouses first and then you can supportively commiserate. Baring that, stick to content comments. Pointing out typos is not helpful unless you are reading galleys. You would probably be the eighth sharpie to do so, the 'publisher' already knows, and there will be no corrections anyway of that kind to 'subsequent editions' unless you are ... well, no one gets that kind of customized attention to typos once a book has gone through a first run.

I would think it would be perfectly acceptable and somewhat expected for you, the friend, to tell the author about typos. It's not like they're necessarily his/her typos. So I don't see where the potential embarassment or insult is coming from. He should know about it - simple at that (in my opinion of course). I mean isn't the piblisher working for him, in a sense? If I made dresses for a living and a friend of mine bought one, wore it, loved it... but for some reason didn't want to tell me that the department store that was selling my dresses kept putting them on the mannequins backwards... well.

Maybe I'm missing the point. It just seems if it were me, I would tell him, straight up.

'Hey. I really dig your new book. But man, you need to crack skulls over at your publisher's. I counted at least a dozen typos.'

'Really? {passes the ketchup} Mate! Thanks for telling me. I haven't had a chance to check for myself. Did you see the Redskins whoop up on the Giants last Sunday?'

Depending on what kind of typos. If they could be interpreted as grammatical errors on the part of the author -- I would go nuts, personally.

I would definitely say point them out. Most authors welcome this (I've even seen contests online to find typos), because it allows them to get them corrected for future printings.

A person I know has a very European background (born in Yugoslavia, grew up as the child of an ambassador in three different African countries, went to college in England, then lived in New Zealand for several years -- then married a Yank and moved to the Pacific Ronthwest). The publisher of her book, in addition to making her use a different last name because her real last name is "too difficult" for Americans, went through and Americanized her spellings. Unfortunately they were a bit overzealous with the u-ectomy, because they changed "mourn" into "morn," "mourning" into "morning," etc., totally changing the meaning of several passages and making a number completely nonsensical. She seemed to take it in stride when I mentioned this to her (at least, she didn't seem offended) and I believe this is being corrected for the paperback issue.