Das IMA Program
First, its not your old IMA program anymore in that it is changing from the quiet backwater it once was, specifically, you may or may not be on an AEF roster; given the numerous deployments, nothing is sacred, because you can still be activated and sent to wherever the AF wants, as to the probability of that happening, well the last time I talked with the IMA people Jan 2005, they said very few IMAs in fact had been activated involuntarily, in that there are many people who are willing to volunteer. However, changes were afoot as I retired this summer and most of the activations up to that point in time were in critical fields like weather, security-- not pilots.
In your case, where you have been out, simply go to the ARPC website, they have numbers for you to call, or do a search, note a "BIMAA" is a person who works at a specific base managing IMAs, (see Hill AFB they have a smattering of IMA jobs listed). Also you can live and do your job elsewhere, in fact there were no slots at my base, but I was put in touch with the senior IMA officer for my base and he informed that there were in fact slots at my base, they were just on paper managed from the parent command. Failing that, simply call the AF Reserve recruiter and tell them you want to apply for an IMA slot, which are available on the web to view, listed by AFSC, rank, locale, etc--but paradoxically, you have to already be on duty in some form to access the system, but AFRES ARPC people might have since changed that feature.
As to actually going into a flying unit after being dormant for some time, it might have been problematic for some, but I've seen it happen in 90 days for an individual who hadn't flown in 3 years, however, if you're lacking in social skills with the people that actually do the paperwork drill, then I can see why it might practically take an act of god to make things happen, best of luck!