We’re all looking for more resources for parts and ideas. In case you don’t know about it, there is a great resource called Lego Education. Right now I am shopping for parts and I love this site. I can buy sometimes hard to find parts like pneumatics and more exotic sensors.
Plus, you can sign up for a free catalog. There's nothing like getting a Lego Robotics catalog in the mail and keeping it on the coffee table for perusing when not building.