David Tait's PIC resource Page ( http://www.man.ac.uk/~mbhstdj/piclinks.html ) -- This is the grand-daddy of them all. You will spend hours browsing all these links.
DonTronics ( http://www.dontronics.com/ ) -- Good projects and tools
Microchip Application Notes ( http://www.microchip.com/10/Appnote/index.htm ) -- A complete catalog of all Microchip application notes ... this is where you learn the software and hardware design tricks!
Andrew Errington's PIC Page ( http://www.lancs.ac.uk/people/cpaame/pic/pic.htm ) -- Another PIC project page.
PicBlaster PC Programmer ( http://www.techfreakz.org/oldstuff/picb.html ) -- A pretty neat programmer.
Micro Engineering Labs ( http://www.melabs.com/mel/home.htm ) -- The PicBasic compiler from microEngineering Labs will take programs written for the BASIC Stamp 1 and directly (or with minor changes) download to a PIC (pg. 85 PicBasic Compiler manual).