Check out this amazing free, open portal for Houston and Texas area data of all kinds. The Houston Open Data Portal is a collaborative dataset sharing site built on a wiki model (think Wikipedia), where datasets of many types (spreadsheets, text, GIS shape files, and more) can be uploaded, downloaded, and share openly with the public. This is a potentially tremendous resource for Houston entrepreneurs and strategic planners.
Check out the variety of subjects covered on their browse-able datasets listings page, from "City of Houston Funds" to "Proposed Land Development" to Houston Police "Department Crime Statistics" to name a few.
Below: a map image of all sites in the State of Texas that have been designated as Radioactive Waste sites from an entry on the Houston Open Data Portal.