Google Webmaster Guidelines
A great way to learn about Design, technical, and quality guidelines..

www.opuzz.com
Royalty free background music for any production

stock.xchng
Free Stock Photography - Professional and amateur photographers share over 100,000 images for personal and/or commercial use

morgueFile
Free high resolution digital stock photographs for either corporate or public use

bigfoto.com
Royalty free photo agency offering free use of all pictures

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GEek PHILOSOPHER
More free images and an extensive resource section

STOCK ICONS
Over 6300 XP Style Icons assorted in 6 Stock Icon Collections