Car loan and having a weird job?

ok so i need a new car. i just graduated with my bachelors in august. i now work in ecology field research which means i move from job to job to job all across the country. i need a nice used car (im thinking '03 honda civic) to get me to my jobs. i have lots of student loans, no co signer and am not making big bucks. will i be able to get a car loan? i keep getting denied by banks. ive heard dealerships are easier to get loans from but i was hoping to buy from a private seller. is there any way for me to get a loan for this car?