I'm not quite clear on just where you're at right now.
Is your bike a single speed, coaster brake or a multi-speed with derrailleur? (Spelling?)
Multi-chainring type bikes have a longer axle, hence wider dropouts, than single speed bikes. Converting is not impossible, but it's a pain.
I'd recommend just buying a new wheel. Cheap ones can be had for about 40 bucks or so.
And also start trashpicking bikes in the neighborhood so that you have spare parts, like wheels, to fall back on.