These days whenever I tell folks that I am a professional organizer, they have to ask me about the A&E show Hoarders. Generally, my clients are just regular folks with busy lives and basic levels of clutter (basement overflow, an unusable spare room or just an office with too much paper).
In May there was a very good interview with hoarding expert, Dr. Randy Frost, on NPR's Science Friday. Dr. Frost mentioned the OCD Foundation as a good place to find help in the form of therapists.
On a personal note, I only work with true hoarders under the supervision of a licensed therapist and I have only seen about 15 minutes of the A&E show.