It sounds like you're off to a good start.

Well, the size of the lake is generally dictated by the "lay of the land", so to speak. Watershed area and precipitation patterns are a couple of the variables to look at, as well as soil type. The National Soil Conservation Service (NRCS) should be able to help you there. There should be a local office near you.

Fish species to stock is also determined by the size of the lake. It sounds like you are going to have one larger than an acre, so a bass/bluegill/catfish mix would be a good standard choice. Stocking rates will vary based on whether or not you will feed or fertilize, as well as where you are in Texas.

You will likely get a lot of good advice. However, hiring private lake manager to guide you through the lake building process would be a good idea. The sponsor of this fine site would be an excellent choice, and there are others as well. If you are "hands-on", you will have lots of fun managing a lake that was built correctly the first time.