Welcome to the PPHA. Like most things, you'll find a variety of opinions concerning mouth calls verses electronic. I personally like the FoxPro electronic calls, however, some of our sponsor's are makers of mouth calls, so I've been purchaseing a few of the mouth calls and trying them.
Coyote hunting is a very challengeing sport. Its not uncommon to call numerous times without actually seeing a dog. Sometimes you'll actually call one in and not see it. But when you leave, you'll see the tracks where he circled your set.
I'm from York County and have yet to call in a coyote down here. However, I have a camp in Clinton / Potter County and have called 4. Lie anything else, you have to be there when they are.
Good luck, welcome aboard, and happy hunting!