Okay, so I was at Guitar Center today looking for an Ibanez DE-7 and a Schecter C-1 Plus. I got the guitar, but no luck on the pedal.

However, the person who sold me the Schecter said he had a DE-7 in his truck, and he'd give it to me for free.

I'm very aware that the pedal might be shot, but just asking you all to make sure I'm not doing anything wrong.

Guitar > cable > line in. Line out > cable > amp.

I put a new 9v battery in it, and it doesn't come on. When I turn on the amp, without the pedal being on, I hear no sound. I plug the pedal into a 9v adapter (possibly the 'wrong kind'?) and still no cigar with it turning on.

Both cables work.

Anything else I could try, or is the pedal shot?
You could open the pedal up to make sure the input jacks are actually wired. Could be a simple soldering job, could be worse.