I'm a newcomer, so my list reflects that, but my most useful tools are:
1. A drawknife. I like the Arno flat drawknife, which is the one 3Rivers sells although I bought it elsewhere. This will take a board through rough shaping and floor tillering faster than a cheap bandsaw. Touch up the blade by periodic honing on a buffing wheel with a little compound.
2. A spokeshave. I have a few inexpensive ones that work great after tuning up. For that I used a $10 Harbor Freight 4-surface diamond sharpening block. A flat one with help straighten wavy surfaces and a curved one with follow curves. Flatten the bottom and the back of the blade, sharpen the blade, and you have a great tool.
3. Cabinet scraper. This will handle final tillering and make finished surfaces smoother than you can accomplish with sandpaper.