Hey Sledder,
Pork Butt/Shoulder is very forgiving, but like the last poster said, they do take a long time (12 hours a lot of times). I would start with a chicken or two. Whole chickens are real cheap and will give you great practice finding the temps that your grill attains. I know that someone else suggested a good thermometer. I think you will need at least one good, digital probe therm and a cheap oven therm. Keep the oven therm on the grate to know exactly what the temp is inside your smoker and the probe for inside your meat to know exactly when it is done (cook by internal temp instead of time).
Keep researching but most importantly, just start practicing and be sure to post some pics of your smoking, we call it qview.