Finding geospatial data may be easier than you think. Many city, county, and state governments have dedicated data repositories for GIS data; if not, they may have a GIS employee/team that can be contacted to obtain data. The federal government, through its many agencies, also manages several popular data repositories containing a vast amount of geospatial data.
GIS data portals for local government authorities and groups.
GIS portals for the state of Texas, including Texas government agencies.
Imagery can be more difficult to find than other data types. Thankfully, there are many free online databases that allow users to find, select, and download different types of images.