Marguerite's post is a good one. Do the questionaire she suggested, it can be helpful. My difficult child just misses aspergers by a couple criteria, but he is definitely on the spectrum. From all the reading I've done, before we got the official diagnosis our difficult child's therapist was working with him from an autism spectrum standpoint. A lot of social skills type stuff. Even without a diagnosis, as Marguerite said, treat it as such as the interventions can be helpful without the "label".
I would suggest trying to find a psychiatrist or neuro-psychiatric specializing in developmental disorders. I think that sometimes if they don't have 100% of the criteria that sometimes it's dismissed, but it's a broad spectrum.