Aspen is one of my fave places in the fall.( actually up there this week)..and i go there often..and just got back from the Vail, Glenwood Springs area...

  I almost always travel by private invitation...and many summer and fall weekends are spent in the Mtns with fave company.  It's a hike, so most arrangements are more than an hour of commitment for the travel..  I suggest making sure that you connect well in advance with a companion that suits your fancy and simply ask. Last minute doesn't work well up here.. as yes, there are very few legit options but not if you plan in advance. Enjoy