Pizza on the grill is super easy. Pile whatever toppings you want on premade crust (I like the individual size, pre-baked kind) and pop it on the grill until the cheese is melted. The premade pizzas that come refridgerated from the deli section in the grocery store would probably work too if you didn't want to deal with making your own.
Here is a good sausage recipe. It can be premade and sealed into packets so it's ready to go. It takes a bit of time to fully cook, but you could probably get already cooked sausages to shorten the actual cooking time. It's good with some nice crusty bread.
Big Ol' Mess
1 lb smoked sausage, cut into chunks
3 jalapeno peppers, sliced
1 green bell pepper, de-seeded and cut into chunks (I like to use red/yellow/orange peppers too, for more color)
1 sweet onion, peeled and cut into chunks
1/4 cup Tabasco sauce
10 ounces sweet and sour sauce
Make an aluminum foil bag. Use 2 12" x 18" sheets of heavy-duty foil (or double regular foil) and, (after the ingredients are in the bottom half), crimp the top half on.
Put the sausage, green pepper and onions in the bottom half of the foil bag.
Mix the Tabasco up with the sweet and sour sauce and pour it over the sausage mix. Seal the foil bag with the top half. Make sure it is "leak-proof".
Place on the grill (gas or charcoal) and cook for a total of 45 minutes, turning after each 15 minutes.
You can slit the bag open when done and serve from it at the campsite.
If you are cooking this in the hot coals of a campfire, reduce the total cooking time by about 15 minutes and turn every 5 minutes.