Just Google gay clubs Houston. Add Montrose (for Montrose Section) to your search criteria to remain a little closer to the center of Houston, versus outlying areas.
Gay club turnover is fast. The only one I remember still showing in the hit list is the Ripcord, essentially a stand-and-pose leather bar. In the heart of Houston is Rich's, which used to be the biggest. Huge dance floor, stage, great shows, about 7 bars on 2 levels. Online gives conflicting info about whether they are currently in operation, evidently closed for a time. Phone first.