schematics anyone?

I apologize now if I'm in the wrong forum, but i'm not sure where to go. I was wondering if anyone out there would know where I should go to find schematic diagrams for electrical devices? I'm taking a 2 year Electrical Engineering program at a community college and I'm required to build three projects for my Design and Fab class. My teacher wants us to go out, find schematics and construct a device using them. One project has to be a dual-polarity variable DC power supply with a fixed voltage of 5V and will be able to deliver @ 3 amps. The other two projects are to be of our own choice. They can be basically anything, but they have to have some degree of difficulty. We also, must be able to demonstrate in class that they do function so that limits the critera somewhat. I've tried different searches on the net with minimal sucess. I've also tried a Walden book store and Barnes and Noble book store. If anyone has any idea of where to look PLEASE!!! let me know.

 

http://www.repairfaq.org/sam/samschem.htm

http://members.tripod.com/xexorz/schematics.html

check these 2 sites, I got these 2 sites by doing a search on...

http://www.metacrawler.com
and searching the word : schematic

Let me if this helps.

 

Thanks for the reply, dkerr. I tried the two sites you had listed and although they weren't much help, metacrawler was. I found each search engine you use delivers different results and I did have some success using metacrawler. I was using msn search before and didn't find much. Thanks so much for the help!!