I know of Boulder Indoor Cycling in (you guessed it) Boulder. They have a velodrome track with a mini MTB obstacle course in the middle and a seating/viewing area at the top of the velodrome track. It's frigging sweet. You have to be a member I believe or pay an entrance fee but track bikes are free to borrow. If they don't sell them, then they would certainly know of somewhere that does. I would call them first to make sure if I were you so you don't have to make the 40 min drive for nothing.
Here is their website:
BoulderIndoorCycling.com
Last edited by Road MTB; 08-13-11 at 01:11 AM.