Can anyone tell me what a MDJ charge per hour in vaud, and also what is the best way of finding one?

It depends on your joint income, as a family. Go to your commune and inquire about the department you have to sign in (waiting list, watch out). You will register, and then depending on your situation (if single mo, with a partner, working and being taxed in the actual commune or out, working for the canton, etc etc), you will have a placement with MDJ.

See some related threads here on MDJrs and day care in Switzerland, just log on whatever you search for in the search windown.