Right now, your approach is a bit backward. If you are determined to build a bike from the frame up, I suggest you do your homework a bit and know what you are doing before launching into it.

You are much better off hunting eBay for a specific frame than using your random scatter-gun approach. Figure out what kind of bike you want to build (XC? AM? A little in between?) and then do some research and decide what frames would most fill that bill for YOU. Create yourself a solid list of a half-dozen specific brands/models that really trip your trigger, THEN hunt for those particular frames in the size you need. It may take a while but you will: #1 get the proper type of frame for what you want it to do; and #2 get the best frame for the money spent.