Hams come in many different shapes, cuts, containers, and states of readiness. A butt-portion ham will have a small bone in the center and generally more lean meat sections. A shank-portion ham will have a large hinged bone in the center and generally have more detours and connective areas. The shank-bone, however, is great for making soups and beans etc., especially after being smoked. I got a "whole" ham once and I remember it was awesome, but don't remember what kind of bone was in it....probably somewhat of a long shank.
Avoid the "canned" hams if you can (oooh, bad pun). These hams are usually full of water and I feel they are of lower quality. In the middle of the spectrum is the kind I usually get, the grocery-store cryovac'd hams. These come in various states of readiness...."uncooked", "ready to cook (i.e. partially cooked)", and "cooked". The "uncooked" and "ready to cook" hams must be brought up to over 150° internally during cooking. The "cooked" variety is ready to eat and just needs to be warmed up a bit. During the holiday season, I can find some great quality grocery-store hams for $.59-$.99 a pound.
On the premier side of hams is the "country style" ham. From what I've read, I believe the Smithfield Country Style Ham is one of the better ones. These hams are dry cured and very salty. We're not going to cook with those today since I know virtually nothing about them other than that they exist and can be quite expensive...but quite delicious from what folks tell me (please, no flames if I'm wrong...but educational email is fine).
Unwrap, maybe rinse if you want, maybe soak if you want...otherwise, that's it. The reason I suggest soaking is that some hams get quite salty from all the water loss during smoking. You won't really know until you try one, but after you get a baseline saltiness figured out, next time soak in some cold clean water accordingly. Again, since saltiness is already an issue, a rub would be redundant and could be overpowering in saltiness. A marinade is an option if you're so inclined, but try it neked once and judge for yourself. The cobsmoke and hickory give it a great gentle sweet flavor that you don't really want to mask with a fancy marinade.
Take a few corn cobs that you've dried out, soak them (yeah, I don't know why you'd dry them then wet them, but this is what I'd do). Put on a couple good chunks of hickory, use clean water in your water pan, and cook your ham to temp.
Generally, about an hour per pound is good...some even quicker. Just make sure to cook it to over 150° internally. Try that, and see if you like it....I do.