Jerry, Two shops that I know of are Vecchio's at 1833 Pearl St. and University Bicycles at 839 Pearl St.. University Bicycles has old bikes on display and I am told that the owner has a fondness for the same. Many of his employees (in my experience) are clueless though. Vecchio's people will have an interest in older bikes and there are often a few on display. Most Boulder shops seem more interested in the recreational and/or MTB customer. If you take a bike with you, you will find many routes to choose from.
Paul Patzkowsky Longmont, Colorado