Interest rate /car loan question

[Myrina]

Hi! I am so pleased to find this group!!

I have been working to repair my credit score over the past year & am finally in the 'good' range.
Mortgage, student loan and a small credit card ($500 limit, $120 balance) have all been current for +1 yr.

I recently talked with my insurer (State Farm) to get a quote on insurance for a used car I'm looking at, and my agent mentioned "Hey! We have car loans too!" so I figured what the hell & let him run me a quote.

The terms I "qualified" for were shocking. The car is a 2008 with 27,000 miles on it, blue book is $21,000, dealer is asking $19,999.
I would be selling my current car outright so putting about $5k in cash down, therefor only needing to finance about $15k.

The loan was 48 months (max for that old of a car, he said) and my interest rate was 10.5%!!!! With good credit???
Are they kidding?

What could possibly be the reason behind such a high interest rate, and would I be better off trying thru the dealer, or - since my credit now has the hard touch from State Farm - am I screwn for 6 months?

Thanks!!!!