1) use the search function at this site to study: oil change, FSS, Topsider, No Dipstick, fleece filter, Mobil1

Some Mercedes have and don't have dip-sticks.

2) you'll need a filter wrench to loosen the filter. there is a Mercedes Part # for it and you can see it at the BUY PARTS tab on the top of this page.

3) some people suck the oil out of the non-existent dip stick, stick tube with a suction device, TOPSIDER or MITY-VAC.

4) you can buy a dip-stick tool that is a Mercedes Benz tool for checking the oil level.

5) you can use the dash display for checing the oil.

6) You may wish to get a new cap for the dip stick tube that has no dip-stick.

If you decide to drain the oil from the sump you'll need a 13mm socket for the drain and a new washer, plus a 8mm socket to remove the under engine encapsualting panel. I'm not positive of the socket sizes for your car.

Use the oil amount listed in your owners manual for refilling minus half a quart, then you can fine tune the exact amount with the dash oil level display.

Have any questions?
E500 is a real fine car, your lucky!