If I'm looking for a second hand fixed gear bike on eBay, what should i look for?
much too big a question: depends what you want, for example, and how much you have to spend. use the search function ^ up there^ to look at what has been written about frames, wheels, etc; it'll take some time but you will learn a lot and then people will be able to give you more specific advice. the only thing everyone will tell you is DO NOT BUY A UNIPAK, the £200 or so ones that are always being sold on e-bay: search Unipak and you'll see why.
much too big a question: depends what you want, for example, and how much you have to spend. use the search function ^ up there^ to look at what has been written about frames, wheels, etc; it'll take some time but you will learn a lot and then people will be able to give you more specific advice. the only thing everyone will tell you is DO NOT BUY A UNIPAK, the £200 or so ones that are always being sold on e-bay: search Unipak and you'll see why.