Personally, I don't like ramps. For starters, they are a pain in the ass to use, and second they are not as practical as jack stands. For a LOT of repair, you need to remove a tire to gain access, or to just give you more room. Try removing a tire while the car is on ramps.
As for using 2x4s....no offense, that is just stupid. I am not one of these "safety police" running around the boards, but seriously, that is a really dumb thing to do. Go to Sears and get a nice set of jackstands, and a good jack. Here is a nice set for $99 at Sears, comes with 3-ton jack and stands.
Jack and Stands at Sears
Or you can go to your local parts supply store, they will have stands and jacks. Also try WalMart, they usually have great deals on combo sets. I bought mine from Sears, it came with a 4-ton jack, and (2)6-ton stands. It was on sale for $69.

Money well spent.
As for changing your own oil, as stated above, it is easy. Put the car on stands, place drain pan under the drain plug. Use an open face wrench to remove the drain plug, and let it drain. I let it sit for about twenty minutes while I am doing other things, just to make sure most of the oil is out of the car. Replace the drain plug, and remove the oil filter. Do this with a filter adapter for a socket wrench, makes life easy. As long as you do not tip the filter upside down, you will not spill any oil. I literally do not get a drop of oil on the ground when I change my oil. Before putting the new filter on, take your finger and smear some oil on the filter seal. Then fill the filter up with fresh oil. You can fit about half a qt of oil in a filter, and it will not be filled up all the way. Basically, you want the filter material to absorb oil before you put it on the car. Add oil, lover the car, run the engine for a few seconds, check oil.