Hi, don't know if this is the right post, but I'm looking for some good books and/or resources about user interaction with web sites. Especially about how to do things, why and more importantly why not doing things. Especially when it comes to web 2.0 stuff like Ajax etc... Because all these new technologies are very cool, nice and fancy when you read about it, do examples and see presentations, but when it comes to develop a real application that needs high performance and other things that are used by people from morning till evening, we find out that about 80% of those cool stuff becomes completely worthless, up to very enoying for the user.

And since I am on the entire process of web application developing (database design, architecture, interface) and have often meetings and talks with the end users, I want to enhance my knowledge about this side of web developing as well.

There is a really good book on accessability that I've recently read.

It's called
Design Accessible Web Sites.
with Jeremy J Sydik

It explains a lot about why use certain techs and why not

I like Jenifer Tidwell's book, published by O'Reilly: "Designing Interfaces: Patterns for Effective Interaction Design". It's especially relevant to web-site design.  The book deals with general design principles aka 'patterns'.  Lovely book to have - almost coffee-table fodder in terms of its appearance; but it also has good content.

http://jtidwell.net/

http://www.amazon.com/gp/product/0596008031

For web UI design see the master Jakob Nielsen

Designing Web Usability

Prioritizing Web Usability

Homepage Usability: 50 Websites Deconstructed

Eyetracking Web Usability