You are pretty much limited to one of the private used car dealers that have signs: “buy here, pay here” signs. But beware that these type of dealers and locations of “JD Byrider” often get a large down payment and overcharge you overall so know the value of the car that you buy. Check edmunds.com for a good source on what you should be charged for a car. These dealers tend to pray on those with bad credit and depend on getting a large down payment and hope you miss a payment so they can repo your car and sell it all over again.
You can go by a used car dealer at a GM or Ford Dealer and ask for the finance manager and see if they will provide you any options (generally higher down payment and higher interest). I would also go talk to a credit union lown officer and see with your down payment would they make a loan for you. Good luck!