Just get your filter from your local store. If they dont have it, Advance Auto or any autoparts store should have them on the shelf. They do around here. When you buy the filter, there shoud be a new o-ring included with it. This will replace the o-ring on the oil filter cover. Remember to dab it with motor oil to prevent leaks, and from melting to the case.
And remember what way the oil filter goes in. Some filters will say "THIS SIDE OUT" or something like that, but others wont. And dont forget the spring that goes behind the filter.
Dont worry about the second filter inside the motor. This should only be replaced/cleaned if the motor is ever disassembled or rebuilt.
This might sound complicated, but its one of the easiest filters to change of any machine out there.
[20:55] <waterpumper> putting a racing pipe on a Foreman is like putting a high dollar bikini on a 400 pound chick...just because it fits doesn't mean it looks cool