Are you planning to buy or lease? As Veronica mentioned, you should find a Realtor that works in the area of town where you would like to live. The Houston Metro Area is huge.
Houston is over 600 square miles large. If you provide a zip code or general area of town you may get a better response to your request. Realtors tend to specialize in specific areas of town rather than all of Houston.
Also HAR does have a Find a Realtor tool, where you can search for a Realtor. http://search.har.com/memberfinder/