There is a wealth of valuable resources on the net - it's all a matter of being able to find them. This is a categorized collection of web design resources I've found useful. Ten random entries appear below.

StockVault
StockVault has good shots, but is new and still has under 1000 professional and amateur photos. Images are medium-resolution, and are browsable by category rather than by search. Personal and non-commercial usage only.
DevGuru HTML Tag Reference
A good listing of HTML tags along with each tag's core attributes
PixelPerfect Digital
Over 3,000 photos and textures, free for use in professional web design.
Pixel Fonts
Teeny tiny bitmap pixel fonts for web designers with little screen real estate
CSS Help Pile
Links and Discussion about CSS Resources
Web Standards Awards
Web Standards Awards showcases the design of sites that adhere to web standards.
Blakems "My Favorite Javascripts"
A blog entry with a listing of some useful scripts
PHP Source Code Snippet Library
A Wealth of stealable code
Glish CSS Layout Techniques
Some nice cross-browser css-based templates for you to steal.
W3C's HTML and XHTML FAQ
A good FAQ by W3C on HTML and XHTML