Where might these designs be?  I'm looking into building my own pad for relatively cheap. 

What kind of pad do you want to build?  I haven't build a pad in forever, and that one turned out pretty crappy because I only spent $10 on parts because I'm cheap and don't care enough about DDR to invest heavily in it again, but pads are deceptively easy to build if you just go with a simple design like CF's or BeatGear's.  I built mine using the CF design from scrap wood, a spare control box, and $10 in wood glue, masking tape, and drywall screws.

Well, let's just say it's permanently broken now... due to various causes.

how about telling us what's wrong with the pad?