The following links are useful for both Photoshop Elements and Photoshop.

Discussion Groups
Photoshop Elements - User to User Forums (if you are new, either log in as Guest, or register for an account)
Pixel Parity (Photoshop discussion)
RetouchPRO Forums - Photoshop Elements Q&A
Yahoo Groups:  Digital Nuts
Yahoo Groups:  Photoshop Elements

Free Online Tutorials
Adobe Education:  Photoshop Elements 2.0 Online Course
Apple - Creative - Photoshop Tips and Tricks
ASAP online: The Concepts    (Photoshop beginner's tutorial)
Computer Darkroom
The Digital Dog    (mostly a commercial site, but contains some free tutorials)
Guntcher Graphics - Basic Digital Photo Manipulation
Janee's Photoshop Tutorials   (also contains a discussion board)
Jay Arraich's Photoshop Elements Tips
Mac Design Online
Norman Koren Photography:  Images and tutorials   (lots of scientific info on this site!)
Photoshop Elements Resources   (warning:  free tutorials, but site contains some commercial content)
Photoshop Elements Tutorials
The Photoshop Guru's Handbook
Photoshop Tutorials
Polykarbon   (mainly for line art)
Robouk Designs Photoshop Tutorials

Free Tools
Actionfx   (contains some free tools and tutorials, and some commercial stuff)
Adobe Studio Exchange    (not specific to Elements, but there is some Photoshop stuff here)
Downloads from Paul Shipley
EKNP Free Fonts    (currently not available)
Free Photoshop
The Hidden Power of Photoshop Elements    (mac and windows)
Photoshop Plugins

Software Support
Official Photoshop Elements Support Page

The Computer Darkroom's Colour Management pages
Digital Camera Reviews/Previews   (warning:  site does not display properly in all browsers)
IrfanView   (a free graphics viewer for Windows)
Scanning Basics 101 - All about digital images
Scanning Resolution Calculator

And once you've learned a few things, try showing off your new skills by participating in The Challenge.
It's free and open to all.