Frank,
Right now, you're kind of on your own looking for the best way to contact Allen. The only current number I know of is: 847-877-5853, but that's a cellphone and he rarely, if ever answers it, plus he doesn't do email. And I don't think anyone has a mailing address for him as of yet.
Earlier this year I bought my Theoben through him and have been trying to reach him for weeks, or better said; months, in order to buy one of his flip compensators, plus to discuss a few questions that have come up. I have even briefly spoken with him a couple of times, but each time was told to call back in a week or two because he was just too busy to talk at the moment. I have done as he asked, sometimes two or three times a week, with no return calls.
Be patient as he has a lot on his plate right now, and hopefully he will be able to get his life back in order very soon.
Dave Shattuck