The CAD Block Exchange Network
Cben.net is are really usefull website for anyone who uses an AutoCad program. The site is like a digital libary of CAD designs, uploaded from from users like you. So you can either uplaod your design for all to see or borrow someone elses.
It's kind of hard to find the exact thing your looking for because anyone can download the design ur looking for and might not give it a good description. The nice thing though is you'll probably find something cool on the quest.
Overall this is a goodsite with a bunch of cool designs, even though it is rough to navigate. Also thisa good site for beginners to look at all the stuff that can be done on CAD. Just remeber they would like you to share some of your designs too, mayvbe you could help someone else out