Yeah, I built my first three or four wheels w/out a stand or tensiometer. Since then, I've been working with a cheap $30 minoura spaghetti truing stand, and wheels come off just fine. I made my own dish tool out of plywood.
I recently got a Park TM-1 tensiometer, and it's a fun little tool. I use it a lot more than I need it, but it's certainly nice to have. Overall, you're probably on the right track... tensiometer > truing stand, but patience and attention to detail will get you further than both.
I still true my friends' wheels in their frames just for convenience (pre-ride: "dude, you're almost rubbing your brakes there").
Make sure you have a printed copy of Sheldon's wheelbuilding page on hand -- it's really handy for getting started with the key spoke so your hub ends up in a nice orientation and you have good valve stem access. Good steps on which set of spokes to insert into the flange when.
Good luck!