I know you can use dpdt and 3dpt to get true bypass but I was wondering if there it a way to use a spst switch as a on off switch for pedal, I have like 17 off them just lying around.
Yes, but it's not true bypass and I don't believe you can use an LED. But you can try this idea. Look at the second schematic on the page.
http://www.muzique.com/lab/tsbuff.htm (http://www.muzique.com/lab/tsbuff.htm)