I don't have an sd card for my mytouch 3g HELP!!! What should i do?

So my uncle got me a mytouch 3g but i think it was from a pawn shop or something like that. It had someone else's google account and everything but i did a factory reset and reset everything. So i set that up, but the phone didnt come with a sd card so i can't save anything to my phone. What should i do please help!!!