CNC Companies
From HacDC Wiki
I've used eMachineshop to cut 200 plastic bases I needed for a project. Pretty happy with the results and pricing. I used their (proprietary) CAD tool which then can price an order and place an order.
Here's a company that specializes in low quantity runs and prototypes. I don't know too much about them, but it seems like that fast quote system might be nice.
Protype, Reston