I´m not up-to-date if there are numerous "newer" book, all I read was Caro´s Book of Poker Tells and "Read´em and Reap" from Joe Navarro. Both books contain "interesting" and probably (from an academic point of view) correct stuff, nevertheless I wasn´t really able to take anything helpful for real live games. It might have been my fault though ... :|

I'd highly recommend you check out "Reading Poker Tells" by Zachary Elwood (published 2012).  The book covers a lot of different things to watch for and can help both in spotting tells in others and also in avoiding giving off tells yourself. It is very well written and an easy read. Picking up on tells will never be one of the stronger aspects of my poker game but it is something that I am much better at now that I have read this book.

I've read Mike Caro's book but didn't get much from it. Annie Duke has a poker training video that covers poker tells but I did not find that especially useful either. I am not familiar with the Joe Navarro book.

Read em and reap is 80% crap filler, but the 20% is really good and well worth reading. I don't like Mike Caro's book much, I think the tells are quite weak. Joe Navarro has also done a series of videos from wsop academy on poker tells. 

But I know a fair bit about it if you want some advice, It was the first thing I was interested in with poker .

Thanks! nickski444, yes I´m interrested of your advices :-)