I am in the same boat as you, however, I am in the hiring process for the Diversion Investigator position with the DEA. To give you an idea of how long I've been in the hiring process, here's my timeline:

12/02 Mailed resume to DEA headquarters.

03/03 Oral interview.

05/03 Preliminary reference check (they contact the employers you list on your resume).

07/03 Received background information packet via FedEx (SF-86, SF-86a, and the addendum to the SF-86). Fingerprinted, drug test, and medical exam. Sent in the completed forms.

It's now Sept. 2003 and the DEA is still doing their background investigation. The recruiter said that the background investigation usually takes anywhere from 2-6 months depending on the number of places you've lived and how many jobs you've held.

Hope this information helps.