Please Please PLEASE,do whatever you can to take a lesson before buying a rod. Some shops used to do a kind of informal, free, group casting lesson on a weekend morning. And remember, if you ever want to visit that shop again, please buy whatever you end up wanting from that shop. You will be treated much better in there upon future visits. Most shops will also invariably throw in some stuff now and again (usually flies or leaders or thread if you end up fly-tying as well...small stuff but hey) during future visits. As was mentioned, if you could find a "club" in your area, it would serve you well. Not sure if there is one real close to you or not, sorry. Texas Fly Fishers is in Houston, and could become a great resource for you if you can travel there.
If you can't find a casting instructor close to you, pm me and we'll try to work something out.