http://www.pilotdomiciles.com
Your choices for Denver are SkyWest, TSA, and GoJet.
I can only speak for SkyWest, and you will most likely get Denver within 6-8 months of getting hired, but as always, things are always a moving target. I keep hearing about upcoming growth in Denver, especially with a lot of new EAS routes that have either already been awarded or that the company has currently placed a bid (PUB, BFF, LBF, LBL, , CNY, and VEL all confirmed, EAR and SLN currently have bids). Also, a new JAX route has been announced.
As far as Houston, Expressjet is very senior there, and SkyWest has shrunk that base considerably and it is senior as well. Some FO's were recently awarded IAH at SkyWest but it is not very common. Mesa has a huge presence there and all hires on the E175 go to IAH currently.