Hi Garrison,
Just a few thoughts of very basic information to add to the advise above.
First, and you may already know this, but, rod weight is a big factor. The bigger the rod weight, the heavier fly line it takes. From a practical consideration, a light rod is nicer to use for a delicate presentation and is a lot of fun to use, but the heavier rod will handle larger fish, cast a heavier fly (like a big stonefly nymph if trout fishing), and handle wind much better than a light rod.
If you are going to use the same rod for redfish or specks, go for the 6 weight. It will do much better than a 5 wt. for the salt, will handle the wind much better, and will do fine for trout.
A second factor is the rod action. A fast action means that most of the flex in the rod, when casting, is in the tip. A slower action has more flex further down the length of the rod. The advantage of the faster rod is that it will throw tighter loops than will the slower rod, but the price is that it is much more difficult to master. I think that virtually any beginner will be much better of with a slower rod. Most of the mid to higher priced rods tend to be fast action.
Another factor is rod length. For a brushy stream a short rod is much better. The Cimmarron, where I fish when I can, has quite a bit of trees and brush around it, and I use my very inexpensive 6.5 foot when fishing it. It is a $25 yellow fiberglass Eagle Claw rod, and a joy on that steam. For open country, a longer rod is much better. I think if I wanted a rod to fish for redfish and specs, but also wanted it for trout fishing in the mountains I would buy a 9 foot 6 weight. For my trout fishing I would avoid brushy tree lined streams, and would find out where some good meadow fishing was, and would go there.
Another factor is that for the salt, you want a corrosion resistant rod and fly reel. Many rods and fly reels are not corrosion resistent.
Finally, I am very much in the camp that says buy the rod now. Fly casting is about 10 times as difficult to learn as using a spinning rod. Get the rod now, buy a video on fly casting, and practice in a park or football field some before you go. My first fly fishing was miserable because I had done no fly casting prior to fishing, and even with some instruction from a friend, it was pretty much miserable. Practice before you go. Also, if you have access to a pond or lake, try some bluegill fishing…great practice, and a lot of fun. Even ponds in a park in town can be pretty good.
If I were to start over as a beginner, and at the same time know what I know now, I would look pretty hard at a Cabelas house brand “Cabelas” rods, in one of the fairly inexpensive models. You get a lot of rod for the money. You might even phone Cabelas mail order line, and talk to one of their product experts on fly rods. The expert will know which rods and fly reels that they have that are corrosion resistent.
There may be fly shops in your area that will also have similar rods. It doesn’t hurt to look. However, if the shop tries to sell you a $500 rod, I would walk. (Knowing what I know now, I would be suspect that such a shop is far more interested in their bottom line than they are interested in what is best for you as an absolute beginner.) Such a rod is likely a fast action, and not a good choice for a beginner. The very experienced fly fisherman in the shop may really like such a rod, but that doesn’t mean that it is a good rod for you.
If the shop has a middle aged or older guy that has taught a lot of fly casting classes for beginners, and taught a lot of beginners to fly fish, he will be a lot more aware of what would be good for you than will the young employee in the shop who has fished enough to learn to be a pretty good caster, but doesn’t realise that the beginner will have a tough time with that super fast rod that he himself likes. Just because he likes that super fast rod does not mean that you will do well with it, and in fact that super fast rod will make it a lot harder for you to learn.
Anyway, my two bits.
Regards,
Gandolf