Here are a list of websites and other places that we tend to linger at for great advice, parts, and/or news.....
Hack A Day is a great place all things hackable both electrical and non electrical.
Digi-Key is a standby for your electronic parts need.
Mouser is another standby for electronic parts.
Batch PCB is great for all your prototype PCB needs.
A fine site for the Engineering community.