Anyone in the area should stop by, there is usally some pretty good stuff there. I know there will be people coming from Wyoming, Eastern Nebraska,Iowa, and last year we had someone Minnesota show up to sell. BTW this not my event I just know the promoter and I will be selling at this, so I'm trying to get more people to show up.
http://www.oldbikeswap.com/Swaps/Boulder/
http://www.oldbikeswap.com/Swaps/Boulder/