In what range would my interest rate most likely be for financing a 30k used car? My credit score is......?

My Experian is 634, Equifax 627, and Trans is 620. I have a few late payments that are on my credit report, most recent late payment was in Jan 07. Prior to this the latest late paymt was on Aug 06. I have a secured credit card $200 limit which I use every month and always pay it off at the end of month. A Macys card with a $300 limit with zero balance which I also use often and pay it off at the end of the month. I have two installment loans one for $241 a month which I still owe $4000 on, and one for $93 monthly for $2000 which I still owe $1700 (just opened it). I also have a student loan which I owe about $3000 and pay $50 every month. I do not have any accts in collections at the moment. I always keep no more than 25% bal on my accts. My history is about 3 yrs old. Im thinking about financing a used car for 30k and would like to know based upon my credit details/score how high would my interest rate be? I don't want to get a high rate. Professl in the field or Persnl Exp Pls Help.