I really need help!!!!

let me just say this. it ran fine three weeks ago. i went to school came home during the weekend when it got really cold up here in ny and then it was not working, right. i did have to put a new muffler on the car recently but again it ran fine after that and now nothing. does this mean i have to rebuild the carb? if so where can i get a kit to rebuild a one barrel?
thanks again
-marc