I'd go with the suggestion on getting some 1 oz. bulk samples from SP. The two most common base tobaccos (base being the predominant tobacco on which a blend is based) are Virginia and burley, so I'd get a sample of a basic version of each of those, to learn their tastes.
For a year or two, I wouldn't buy anything in quantity, even if you like it, because your tastes will change, probably a lot. Keep it to a pouch, an ounce or two, or one tin.
Anything you don't like, put in a canning jar and save it for a year or two. Come back to them later; you'll taste them very differently.
Mostly, don't stock up too much. Take it slow and easy, and work on technique and enjoyment. Study the tobacco pages online so you learn a lot of brands and blends, but don't buy too many to start.