The J-1's I've been familiar with have all been 18 month max. So, yours is an unusual situation (J-1's are unusual anyway, there are no more than a couple thousand of them a year, unlike H1-B's which are in the 100,000 range); you'll need either an immigration lawyer who has experience with J-1 or a good contact at the INS.

As jpdx mentioned, normally there is a sponsoring organization like AIPT, and they handle all the paperwork. (they also offer very inexpensive health insurance for the people they sponsor, so that is a great benefit). Note the "global reach seminar" link on their site- they give J-1 seminars.