FloorPro
Some people don't like the scrubber (vs extractor), but I've had the best results with the Electrolux FloorPro. You can get one on ebay for around $100, and they clean up perfectly if they've been used at all. I think a lot of people don't use them more than once before they're sold. The last shampooing I did was with a Kirby, and it works well, too. If you really want an extractor, of course these won't be appropriate.