Please visit Houston Association of Realtors and they will be able to assist you. There are several locations around town, so visit HAR.com and find the location closet to you. I hope that this helps!
You must join HAR as an affiliate and then apply for a key. The link to apply for an affiliate membership is https://members.har.com/joinhar/DispAffiliateSignupForm.cfm Hopefully that helps!