Dunno where else to put this since these are tutorial books ;D
But go here for anything tech related. They are expanding. Currently they are limited to coding, Linspire, and OO.org when it comes to Linux, but it is growing.
Concept is great -- PDF is free. For screen viewing that is. The high quality print shop quality one is a few bucks.
LinuxVillage - The truely community run Linux/Floss forum !
No IT BS !!