When i first brought it up to my psychologist, who i'd already been seeing for awhile(but it was for some issues, not necessarily focusing on social stuff at the time, so no specific diagnoses were really being discussed at that point. before i knew about AS, i pretty much still thought that i was just weird and had anxiety), i just said that i had read about something called Asperger's Syndrome and identified heavily with the symptoms. She said that she did recognize a lot of AS symptoms in me also, so the next couple times i saw her we went through a checklist and talked about the criteria and stuff, and she was pretty sure i had it. So, i took the big psych evaluation with the IQ test and all, and she got some information from a past psych eval i'd had(which came up with "personality disorder NOS" by the way.. lol.), and after the results were all scored and stuff, she wrote up this long report about me with diagnoses of Asperger's, Inattentive ADHD(which i didn't really expect, actually), Generalized Anxiety, and Depression.
So, i'd say that you should probably just say that you read about Asperger's Syndrome and feel like it describes you.. Tell them which criteria you think that you meet, and if there are other people with it whose experiences you've heard about and can relate to.