Get on the list for the Weld County Fish & Wildlife range, near Ault.
http://www.wcfw.org They are about 10 minutes closer to F.C. than the "usual" spot at Pawnee. Ranges and facilities are excellent. You are welcome at organized matches even if not a member.
I used to be a member at NCRGC, but let it lapse once I joined WCFW.
Other than that, there are a lot of organized events (shotgun, IPSC, 3Gun, steel, revolver, silhouette, Hi-Power, Benchrest) at Weld, Boulder, the Aurora Gun Club, Pueblo, Byers, Ben Lomand (sp).
If you shoot at Pawnee, make sure to pack in your targets and pack out all your trash, and any other junk you can. If you want to shoot long-range rifle in a "field" setting, there are a lot of safe places there to do it, and we don't want to lose it as a resource.
I also have a summary of Colorado practical shooting here:
http://demigod.org/co3g
-z