That is not ucommon for some dive shops to not mention the local diving, they may think that the best thing is for you to call them so they can talk you into comming in to the shop and let them try to get your biz. There are 6 divers from denver ( go to the search and type colorado in state then Denver in city areas) I would suggest contacting them via email (here in divebuddy) and ask them. Diver usually know the best spots to dive and know the local dive areas. If there is an email for the shops, email them too. The ones who respond would be where I would first want to do business with. Remember you should have an altitude specialty class done before you dive there (if you have not done so already). Dive tables are totally different at altitude than at sea level. Dive safe and have a smooth move.