Stock Images
Getty Images - Huge searchable image archive.
iStockPhoto.com - Royalty-free images contributed by members.
Picture Quest - Archive with over 150,000 images.

HTML Guides & Totorials
Webmonkey - Complete web developer's resource site.

Design Help & Tutorials
Designs by Mark - Very useful tips and tutorials for Photoshop, Flash, etc.

Fonts
FontSavvy.com - Nice & categorized font archive.
Acid Fonts - Great collection of free fonts.
Flashkit Font Archive - Over 1300 fonts. Frequently updated.

Scripts & Coding
Java-Scripts - Great little place to find cool and useful JavaScripts for your site!
Javascript Kit - Nice archive of javascripts.
Hotscripts - Thousands of useful scripts. ASP, PHP, CGI, and more!

Software
Adobe - Makers of Photoshop. Great graphics editing program.
Macromedia - Makers of Dreamweaver. Great HTML editor.
Ulead - Affordable shareware graphics tools and more.