I'm thinking of changing my kitchen and bath floor, countertops and backsplash. I don't have all day to create a 3-D model from scratch. Can I start with a photo and visualize changes?
This isn't exactly what you're looking for, but I would suggest that you try Autodesk Homestyler.
An example in design mode
And a feature that renders your design into almost life like pictures!
Loads of items, really easy to use (like "The Sims") lots of calculations and 3D rendering. Its free - only cost is for high definition pictures.