The best information I've gotten has been from other parents.
Not for a diagnosis, but for recommendations. With other parents, you don't have to worry so much about ulterior motive. And most are happy to give you their two cents.
If there isn't a local support group, try going to Yahoo groups and see if there is an autism or Aspergers Yahoo group for your area or state.
Oldest DS, he knows he has some learning problems (although according to the school he is not LD) so that's how we've approached explaining things to him. That we're trying to get some stuff figured out so that he can do better at school, get help if he needs it. He's a little confused as to why this "help" includes identifying facial expressions, but he's going along with it. Our situation is perhaps more difficult in that youngest DS had an autism diagnosis, and oldest DS is very very different, and of course he in no way thinks he resembles his brother.
We don't have an official diagnosis yet, only a screening by the school, so I am in a similar position. I think it depends on where you live. Here, I
know where he needs to go, I am having trouble getting an appointment. I went to the school district's autism coordinator for a screening (hey, anything to help get thru the door) and then called the Dept of Mental Health, who also does a screening. Once that is all in place, they will help me get an appointment for a proper eval. You might find that this happens to you, too, even when you figure out where to go, getting an appointment is hard, or they're booked 2 years out, and you'll need to find some sort of referral by someone, not for insurance purposes, but to even get in.