One of your first stops should be Greater Houston Convention and Visitors Bureau. Here, you'll be able to orient yourself and pick up some great ideas before you set out exploring.
You'll soon discover why this Downtown Houston tourist information center is visited by many travelers. If you're looking for other things to keep you busy, Toyota Center, Minute Maid Park, and Houston Zoo are in the area as well. They won't take you long to get to from Greater Houston Convention and Visitors Bureau.