Bicycle Mechanics - switching 24 inch wheels for 650c?

Hello all:

Newbie here. I'm sure this information has to be somewhere on the internet, but I can't seem to find it! Does anyone know how I can tell if my bike frame which currently has 24 inch wheels will fit 650c wheels?

I am currently riding a supercool old trek 360 which I deeply love but which is just a little big for me--have an old Raleigh kids' road bike hanging around which I bought for basically nothing. It fits like a glove (I'm five feet tall), but it's heavy heavy heavy and needs a few new things.

I'd really love to learn to work on bikes more, and since it's tough to find a good bike for a short person, I think it would be fun to build my own--have a little money to spend but not much, my trek's a singlespeed and I'll probably make this project a singlespeed as well. The problem: really tough to find a small enough frame that I like and that isn't super expensive... And I'm thinking: If I already have this one for free--maybe I can see what the frame weighs alone and then try and figure up what I'd be looking at as a final weight for the bike if I bought all moderately lightweight stuff to put on it.

But it's easier to find tires and such for 650c wheels, so I'm thinkin' of maybe going that route. Anybody know how to tell if they'll fit?

Check Sheldons sizing chart. http://www.sheldonbrown.com/tire_sizing.html
Looks like too big of a difference in size.

I think you're looking at a lot of money anyway by the time you buy some 650 wheels. Those are really only used for competition Tri or track bikes where the riders are often willing to pay whatever it takes within reason. So nothing with 650 on it comes cheap.

Now what you could do is learn to haunt CL in your area as well as Ebay and slooooowly bid on stuff at a price you can live with. If you get outbid then fine, that's one less person that'll bid against you later. Eventually you'll get what you want for quite a bit off normal. At that point you build your bike. It's a slow process but it'll keep the cost in check.

Doing it that way I'd even suggest you bide your time and find a nice smaller frame size tri bike or just a light alloy or steel mountain bike and turn it into a 650 road bike. In particular watch for things like a 15 inch Trek 990 or 970 or 950. These were among the finest steel frames ever made.