A guy posted just recently about how his $4 frame blew up into a $900 touring bike project:
http://www.bikeforums.net/showthread...it-Your-choice
Now, I won't say it wasn't worth it for him. But I will say that putting together your own bike is unlikely, in the long run, to save money -- unless you already have most of the parts available already. Getting a used bike up to snuff can easily turn into a money pit. It's also going to chew up a lot of your time. I don't know your options or priorities, but perhaps doing more work for pay can shore up your funding, both for the bike and future tours.
Also, I wouldn't go for cheap parts on a touring frame. That's a sure-fire route to getting stuck on the side of the road, miles away from civilization, in the rain, cursing Suntour for making crappy components (rather than yourself for buying 'em).
