First, report the claim/case to your motor vehicle insurance company and let them investigate/defend the claim. If you were the titled owner of the vehicle, there is likely exposure. Did you maintain insurance on the vehicle? Did your friend have his/her own insurance on the vehicle? These are questions that need be answered.
Since you sold the auto prior to the accident just hand those documents-i.e. bills of sale etc.. over to your insurance company to defend for you. If necessary they will hire an attorney to assist and to advise you.
You cannot "sell" the car without transferring the title in writing. So, you are liable for all the damages your friend caused,as is your friend. You have a case against your friend for whatever you have to pay.
You should retain a lawyer to defend you, as I am pretty sure the situation would not be covered under any policy of insurance.
This is a summary based on incomplete facts. You should not rely on it as legal advise. No attorney-client relationship is intended to be formed.
As an attorney doing insurance defense work, I handled several cases like this. First, friend or not, you should have gotten something in writing. In any event, you need to be able to prove that you had actually sold and transfered full ownership in the car to the friend. If you can, then you may be able to escape liability for the damages. There is Florida case law on this issue. You need to report this to your insurance company and you might need to hire an attorney to defend you at some point. Good Luck.
This response is to provide general legal information and does not constitute legal advice nor should it be considered or viewed as forming any sort of attorney-client relationship and such information provided is viewable by the general public.
A roundup of the best tips and legal advice.