I'll add http://www.bikepartsusa.com
http://www.campmor.com
http://www.brandcycle.com
http://www.bikeisland.com (No shipping...great service)

BPUSA has a lot of stuff cheap, but can rock you on the shipping...the best thing is to get stuff in bulk from them.

Campmor has stuff cheaper than most places and alot of 'bike specific' or 'bike adaptable' stuff.

Brandscycle has a no shipping price line...75.00, I think.

Bikeisland has a 'tools' section that can't be beat online for the DIY cyclist/mechanic. Good prices, too.

A new site I just discovered from a recent thread is http://www.bicycleclothing.com Going to buy the WP/breathable jacket, pants and helmet cover in a couple of weeks.

I've dealt w/most of the other stores on other posts and can say that any of them are tried and true.