Depends on the therapist/counselor and if they have an opening. When I was calling around last summer, some well recommended therapists had no openings and couldn't tell you when they would be available. Others it would take weeks to get an appointment. We ended up doing the testing with someone who could work with our schedule last summer, and we lucked out that that the psychologist DS was recommended happened to have openings in her schedule when I was looking.

It all depends on WHO you want. If you want someone who everyone recommends it could be months.