So my girlfriend was talking to one of her friends that says she is building up a track bike. This girl has no idea what she is talking about and thinks she can build up a decent one with new parts for about $300. Well now my gf wants build one with a slightly more reasonable budget of $500-600.

Looking around quickly it seems like that would be hard to do with new parts. I was looking at a cheapish leader build but it quickly went over $600. The gf says she would be cool with looking for used parts, but the local cl sucks and we dont have a bike co-op anywhere around here, so I'm limited to ebay.

Have any suggestions on where and what to look at to stay in budget but still have a nice bike, or do you think she should just buy a nice complete bike?
Thanks.