I need a divorce but have no money and don't know where he is.

Search the phone book for a legal aid attorney.

It will be difficult to get a divorce without money. Uncontested divorces do not need a lawyers help, however you still have to pay the court filing fees which can range from $150 all the way up to $300 !
As far as finding him, you would place a Notice of Publication in your local newspaper (you'd need to contact your local courthouse to see which they accept). This should run for 30 days, and you'd need proof of this notice as its considered serving your missing spouse. You would then file a missing spouse divorce, in which he would have up to 30 days (depending on your state) to reply. If he did not reply, it would be granted by default.

Most areas have a legal aid society. They can help you with a lot of the legal work. They charge on a sliding scale ( at least locally) according to your income.

But you will have court costs, publication costs and other costs that will have to be paid.