Mike Caro's Book of Tells is a good one. Not only does it explain all of these tells, it gives ratings on how accurate he believes each one is.
Caro is OK. Joe Navarro's
Read 'em and Reap is a squillion times better IMO though. Better researched and written, better and much clearer images and a hell of a lot easier to read and apply. Plus it skips all the stuff about draw poker home games that's irrelevant to 99.95% of the population.
Just to buck the trend, I disagree with all the people saying tells are overrated. So there.
And as to the neck issue from the OP, you want to be looking at multiple areas, not just one. How is the person sitting, where are their
hands, how are they breathing, how are they acting, and how are all those things different to their behavioural baseline? You can't get reliable information from just looking at the neck - or the eyes, or any other single area for that matter.