How can I divorce someone I haven’t seen or talked since 2001?

As with any divorce, you will have to "serve"your spouse with notice of the proceedings and give them an opportunity to anser your complaint. In a case such as this, you can give notice via "publication". This means that you can put a notice in a newspaper in the area of your spouse's last known location. The court will instruct in what papers, etc. After that, if you still don't hear from your husband, then you can proceed with your case and a "divorce by default" will be granted. Normally, a person can file for their own divorce; most states have websites to walk them through the process. However, your situation is a bit different and you would be well-advised to seek legal counsel in this matter. 
Since money is an issue, there are agencies/groups that provide legal assistance for free/reduced cost for individuals who are income eligible. Legal Aid is one such service. Also, you can check to see if there is a law school nearby to where you live since they run free/low cost clinics that handle divorce cases. Additionally, you can contact the county/city bar association to see if it has a list of lawyerss who will take your case "pro bono" (i.e. for free) or possibly for a reduced fee based on your income/circumstances. Finally, you can contact your local Department of Social Services to see if it can refer you to free legal services.