With no job and no assets, then a Public Defender is the way to go. The PD can negotiate with the prosecutor's office sometimes in advance of your court date, but usually it is done on your trial date. You cannot get these things dismissed ahead of time--you have to let the court procedure grind along.
Public defenders have all of the same rights, powers, and responsibilities as an attorney that you hire. They may have less time to spend on each case, but anything you can do with a private attorney, you can ask a public defender to do.
For more information on me, go to www.kevinpettrey.com. Please remember that if you find an answer particularly helpful, please mark it as helpful or "best answer" so that the attorneys who volunteer their time to answer these questions have feedback. This answer is only for informational purposes, is not legal advice, and does not create an attorney-client relationship. Every case is different and must be judged on its own unique facts.
As a former assistant public defender now in private practice, I can tell you that some of the best trial attorneys are in the public defenders office. That being said, there is only so much an attorney can do with a petty larceny charge. If the facts are sufficient to prove guilt beyond a reasonable doubt, you will be convicted - there's no "first offender dismissal" for petty larceny. However, your attorney should work with the Commonwealth's Attorney to review all the evidence before your trial date - if the case is very weak, the prosecutor may decide not to go forward.
You need to find a defense lawyer as soon as possible. How you go about that is up to you. These other lawyers offer you good advice. But if you want to talk to a private attorney to discuss what it would really cost, many of us will talk to you for free and explain what our flat fee would be given your facts and goals. That all said, here is something you absolutely must be aware of: If you plead guilty to what seems like a good deal, you may inadvertently forfeit your ability to later expunge the record. This is why it is so important for you to get a lawyer for the hearing, then explain to him/her your ultimate goals and concerns.
This is not legal advice: it is intended to be used for general informational or educational purposes only. For a free case evaluation, visit FairfaxCountyCriminalDefense.com.