"What have I done in preparation for a civil suit against the FBI? What are the current obstacles preventing such a suit?"
As well as the FOIPA request process and the administrative appeal process that should follow, the other alternative afforded me by law is to actually bring suit against the FBI, demanding they turn over documents related to an investigation of myself that are known to exist.
I'll just say it straight out: this is not an idea which I relish.
However, my own reluctance not withstanding, at a certain point in the past, around late 2002, I began the research and planning for the bringing of such a suit against the FBI.
I have become quite familiar with the Federal Rules for Civil Procedure (a fun thing to read, btw) and as well, counseled with various professional legal resources as to the best means of beginning such a process.
In the end I decided to not file the civil suit on the chance that I could be held in contempt for something like frivolous charges and thereby have sanctions applied to me that, theoretically, could prevent me from bringing future suit against the agency.
Basically, when submitting to a federal judge a motion to file a civil suit against any federal agency, that judge first, before any discovery processes or otherwise occurs, must deem whether the civil suit is worth pursuing; if the judge finds the request frivolous, he or she can apply a variety of punishments to the plaintiff, known as sanctions. Sanctions can be monetary fines and can also contain other specific directives solely at the discrestion of the judge such as banning the plaintiff from ever filing future suit against the agency in question. Not a good thing. And so, I have digressed in my civil suit processes until further witness data can be gathered.
What I need for the civil suit to work and before I file the complaint document with the clerk's office at the Federal Courts, is sworn testimony from another person, preferably one who had served as a numbered informant, that he or she had been privy to discussion of the investigation of me and especially that he or she had personally observed documents associated with the FBI's case.
Sadly, though not provably, those persons are numerous, most from the social circles associated with my immediate family or my long-term personal friends and acquaintances from a variety of my Houston-based social networks.
This is what I lacked at the time of filing, and so post legal council, I decided not to file until such persons found the courage to discuss publicly what they've discussed with me, privately.
These persons exist; however, for fear of treatment similar to what I have received over the past 5 or some odd years or for simply not being willing to very possibly risk indictment themselves (impeding investigation, informant contracts, etc.), they have refused to offer their public testimony.