Dear Vic,

The average hiring timeline is between one and two years from time of form filling and actual offer of written employment (one without conditions).

The FBI is the type of job you should apply for while you have another job.  If you are currently not employed (and I realize a huge number of highly qualified and educated people have been caught in the unemployment line)  I would not hold my breath for a quick turn around.

Depending on need, budget constraints, retirement ratios, test cycles, and your specialized abilities, it would be at least two weeks to two months before anyone might contact you.   

You need to know that the FBI has put on record that they only process about one out of five applicants initially.  Of those twenty percent initially selected, five percent get through to a final job offer.  The pre-screening polygraph has been attributed to at least one out of two applicants being not processed.  Failing or "not being within acceptable parameters" will for all effective purposes remove you from any federal law enforcement position requiring a Top Secret SCI clearance.  The FBI has been concerned that a high amount of recent SA graduates (past two years) have left the agency compared to previous years.  Some of it has to do with pay, some duty location, and some due to unreasonable expectations of the applicants themselves.

Good Luck.

An FBI employee was quoted by the Philadelphia Inquirer as saying that one out of two applicants do not "pass" the poly.  Of twenty applicants, one gets a job if there are openings available.  For quite a few years, openings were rather slim until 9/11.  It is certainly not a cake walk.