Your best bet is to contact the
BLM and get your hands on Mineral Management Status maps for the area(s) you're interested in. That will tell you what areas are open to mineral exploration. You want the mineral maps, not just the surface ones, so make sure they know that when you call.
From there,
the claim jumping thread will come in handy along with learning how to use LR2000. Of note, LR2000 will not have patented claims in the database, and it's possible someone may have filed a recent claim that hasn't been updated in LR2000 (there's a grace period). This is where walking the ground looking for discovery or claim posts keeps you out of trouble.
Doing a quick check of 010N073W (Red Feather Lakes area) results in 20 active claims showing on LR2000. All but 3 are owned by Astrobleme and what appears to be his family, and I suspect he wouldn't be pleased if folks were searching around on his claims. What's good, is that his claims are all in sections 4 and 12 with the other claims in sections 2 and 32, so there is likely ground available for prospecting. What's not good is there is a bunch of private land mixed in that area (as you can see from google maps), so you'll have to be careful where you're at.
I hope this helps! Good luck out there.