My old tri bike frame cracked and I'm currently looking to strip the components onto a road frame to make a commuter out of it. The parts are 16 years old but have a lot of life left. I just can't seem to find a 650c frame. Nashbar doesn't sell them, craigslist doesn't have them, ebay has tri frames but I'm just looking for a super cheap frame. Any ideas?

look at the BF marketplace and see if any LBS have anything..WTB ad on CL

I've posted on craigslist. I've looked at the BF sales. I haven't checked the LBS though. Good point.

Man, when I was looking for my bike, all I could find on CL were 650C frames.

Check San Diego CL and see of they'd be willing to ship to you.

There was a time (about 10 years ago) when there were a lot of 650c frames - usually women's specific bikes and triathlon frames. They still make them today, but only in S or XS sizes (48 to 50). The major manufacturers (Trek, Spec'd, 'Dale, etc.) still have them in their catalog. Good luck finding one though, they're in rare supply these days.