We live in a 1977 ranch home with a completely straight roof line. The front porch at this time is narrow and inset with the line of the house. We would like to add a roof coming out over a porch - and make the home more of a craftsman style. The house has a full basement and one side of the porch will be higher off the ground. How far should we bring this porch out and how should we deal with the height? All help is appreciated - if anyone has conquered this problem before. Thank you

Check first with your local building or zoning department. There may be a building line or a setback distance from the front property line which would dictate how far, if at all you could build out from the front of the existing house. If the front of the house is built on the building line, you would have to request a zoning variance to extend the porch.
The size of the porch should be proportionate with the existing house. How far to build out would depend on your intended use for the porch. Do you want it to be wide enough for a row of chairs, or would you like it to be more like a room? Without seeing it, it's really hard to advise you. Consider also that extending the roof will reduce the sunlight coming into any windows adjacent to the porch. That could be good or bad, depending on the direction the windows face.
As for the height, some options would be to fill the space between the deck and the ground with wood or vinyl lattice, stack landscape timbers or retaining wall blocks or plant shrubs in front of the high end.