Paper jam in HP 3000

Can anyone tell me what I might try to solve a 'paper jam' error message on
the console? the paper doesn't actually jam, it just feeds in halfway and
then stops. It appears as if the top roller is not turning when the paper
starts through, although that roller does spin at startup when the printer
goes through the self-check. I'm self-empolyed and can't afford any of the
options offered by HP. I'll probably just have to go out and buy a cheaper
printer to replace this one, so if I'm going to trash it anyway, I might as
well try to fix it myself before throwing it out. The thing is only 13
months old and has been used considerable below the duty cycle.