Here are some webpages that you might find helpful in the selection and implementation of your science fair project:

Society for Science & the Public - ( formerly Science Service) a non-profit company devoted to science education.
They administer the Intel International Science and Engineering Fair
and Intel Science Talent Search. They also publish Science News.

New:  Success with Science: The Winners' Guide to High School Research

Magazines Worth Reading

• Popular Science
• Discover
• American Scientist
• Science News
• Scientific America
• Genome
• Astronomy

Other Competitions:

Maker Faire

Disney's Planet Challenge

Broadcom MASTERS - Middle School Competition

Global Online Science Fair - Google

YouTube Space Lab

Pete Conrad Spirit of Innovation Awards Program - High School Competition

Rules Wizard

Pennsylvania Junior Academy of Science

Pennsylvania Computer Fair

Pennsylvania Junior Science and Humanities

Siemens-Westinghouse Competition in Math, Sents.

Dragonfly TV

Some Ideas For Science Fair Projects

Basic Water Information

Student Science Fair Water Projects

Space.com