Tri-Flow oil everywhere it moves, top - bottom and center. Let is soak, turn the hand wheel, give it more oil, turn the hand wheel. If it doesn't free up in a day or two get the hair dryer out and warm it up.
Don't force it. That can bend things.
Belts can be had at your local sewing machine shop or on line at lot of places. My favorite is Sew-Clasic {
http://www.shop.sew-classic.com/ } They also have the Tri-Flow oil.
Like Caroline said, pics will help us ID the machine and give more specific answers.
Joe