Usually, when the perpetrators of a securities fraud plead guilty or are convicted, a restitution fund is set up by the prosecutors. You should contact the AG's office to find out if there is a restitution fund and whether it is still possible to participate in it. It is also common that people released from prison are broke, most of their money having gone to their defense team. so while you may arguably have a great claim against the perpetrators, your ability to collect could be problematic.
Also, you may have a timing problem. Under the federal securtieis laws, a securities fraud case must be brought within two years of discovery (but not more than 5 years after the fraud), and you discovered the fraud in 2005. It is now 2009.
Finally, the amount of your claim, while significant to you, is too small to make it attrative to a lawyer to take on a contingency and too expensive for you to hire a lawyer by the hour.
You of course should speak to a lawyer about the specific details, but it may be that your only practical option is to participate in a restitution fund, if there is one.
From what you describe goven the small amount of lossess and the passage of time, a lawsuit would likely not be economical. Additionally, the potential defendants are likely not very flush with cash after having served time.