Oil Filter Wrench
 

I was thinking of buying my oil at WalMart as suggested by a member here, and buying a filter and gasket set off Ebay and then taking these to a local oil change place to do the deed versus me buying a floor jack.

Would I also need to buy a filter wrench to bring along and insure they use?

The same size cup style oil filter wrench is also used by someVW/Audi, Mercedes, and I forget what else, maybe BMW

Would be strange it they did not have the correct size.

I did the same, (Filter and wrench from Ebay) and I'll pick up two cases of Mobil1 from CostCo. My local mecahnic will do it for $10.
Those oil change places seem to like employ high school workers who don't tighten my oil cap completely so that when I drive away the cap comes off and my engine bay is full oil. Or on another ocassion they left a wrench under the hood, then there's the time two oil caps ended up in hood, etc.