Interest on loans/credit is reported in terms of annual rate, not monthly. This loan at 3% per month is 36% per year. You won't find a credit card in the US at an interest rate that high.
I would not be so sure about credit cards. I was in search for basic credit card when just moved to USA to start my credit history somewhere... I was offered credit cards which are:
1) Secured. I.e. I have to have whole credit line amount as a cash on CD with the same bank.
I'm betting that 3% was compounded monthly too, so the net effect would be higher than 36% - probably north of 40, but I can't be bothered to do the math.