These are easy things to learn that set a foundation for you to learn other things later on also, and leads to not having to pay people for things that you can do. Knowing how to change oil in a motor is something everyone should know.
I know a lot of terms are being thrown at you, which may make it seem complicated, but its not. Generator maintenance is not letting it gum up, and keeping clean oil in it. These aren't hard to do, I am sure there are a million videos online that can show you visually how to do it. You should take a look at some, and you will see just how easy it is, and you'll be happy you didn't pay someone to do it.
Also, having just gone through all this Hurricane Sandy crap, I can't stress the importance of having some extra gallons of gas on hand. The way that situation was handled here was embarrassing. Do not overlook this fact. Nothing would be more irritating than having a generator to power things but no gas to power the generator.