Rob,
I can understand where you are comming from, as I recently was
living a bit far from the stores myself. So, I suggest you stock a
small pantry with items that are used frequently. Then learn how to
substitute and improvise.
Here is what I suggest :

First, get one of those combo spice racks with a variety of common
spices.
Onions. A big bag is cheap, and they last a while if stored
properly.
Potatoes are much the same.
A bulb of garlic.
Cans of tomatoes. I have stewed, diced, and crushed on hand, but
you really can sub any one of these for the others in a pinch. Pick one
or two and keep a can or two around.
A few cans of broth. Chicken or beef.
Oil, but you have that already.
A jar of good mustard. (in the fridge)
A jar of horseradish. (ditto)
Vinegar. It is cheap, and lasts a long while.
A bottle of soy sauce.
Eggs are a bit iffy. They do not last forever, but they are cheap.
Hardboil them if they get near their ending date. This will give them a
bit more time, but lessen their versatility.
Meat is easier than you might imagine. Buy a pack of boneless
chicken breasts when they are on sale. Then put them in the freezer.
Better yet, separate them into smaller packages (two breasts each) and
then freeze them. This works for other meats as well, such as pork
chops, ribeyes, and ground meats. A pack of smoked sausage would've
worked with your rice, and it freezes fine.
There are some dried things that are quite good. If you like
peppers or mushrooms, get a dried pack of your favorite. A few minutes
in hot water will have them ready for the dinner mix. Fresh is better,
but dried is better than none.

Now you have the basics without a huge investement in money or
space. Fresh vegetables are the only thing really missing. Most of
these will last a week in the fridge, and they aren't too expensive.
Buy what you will eat. Also, if you are going to cook soon after going
to the store, fresh meat is better than frozen, if only for the
convenience of not having to thaw it. When you buy something, try to
think what goes with it. For example, if I buy a pack of ribeyes, I
almost always get shallots and mushrooms. Sometimes even a can of beef
consume'. If I'm getting mexican stuff, I usually also get a lime
and/or a lemon as well as fresh cilantro.

Dean G.