Rush Immunotherapy Question

Allergy shots have changed my life, mostly in positive ways.  I feel better, I can keep my wonderful dog, etc.  The only down side is GETTING the shots every week.  With three kids, gas prices what they are, etc., the thought of rush immunotherapy is very appealing.  Additionally,  my upcoming and much anticipated trip to Europe (1 month) will cause a loss of ground in my treatment.  I am very interested in having Rush immunotherapy, but I have a few questions:

1.  Does it work for all types of allergies?  I am allergic to everything (grass, trees, weeds, dust, mold, pollen, our dog, etc.).

2.  I had one reaction to my shots (I take three each time) about a year ago.  About 30 minutes after receiving my shots I started feeling that I needed to clear my throat, then I started itching on my head, on my arms, trunk, etc.  By the time I got home I was covered in hives.  My doctor freaked out when I called him and wanted me to call 911, but I was breathing fine by then and everything resolved without treatment.  I now carry an epi pen with me at all times, but I have never had to use it and have not had another reaction of any kind.  Would that preclude me from receiving Rush immunotherapy?

3.  How do I go about finding a doctor who provides this treatment?  I live in St. Louis, Missouri.

4.  Anything else I should know?

Thanks for you help!
Theresa