I just won an auction for a frame for my first fixie. It is a mid 80s Fuji steel frame that cost me $20 and is local so I can just pick it up. Here it is if you are intersted.
I have mid 80s vintage Cannondale that I can swap some parts over from but I am going to need a rear wheel (unless I figure out how to redish one I have). I may try to rebuild a Mavic MA40 wheel I have with a new hub as a learning experience.
I am looking forward to the build over the next month or so. I am going to use it primarily to beat around with my kids and probably some winter training rides so I won't be putting a lot of money into it.