How big is your service panel? 200 amps? Borderline these days, especially if you don't have gas for some of your needs. 400? Electrical loads have done nothing but increase, so be sure that you do have enough service to be able to implement your plans in the future.

Second, since a lot of the wiring will depend on the model of your tub when (if) it's chosen, don't do the wire. Just plan the route of the wire from the breaker to where you'd want the tub. Then install the conduit big enough and straight enough for that wire to be run easily. And when the time comes, DO hire an electrician instead of the neighbor's brother-in-law. ;) Electricity and people immersed in water can be a lethal mix!

It's cheap and easy to run wire while the walls are open, can be hard and expensive later, depending on access. If you run a bigger wire than you think you'll need and just cap it off at both ends it will be ready for whatever you need. Or you could place a conduit through any finished spaces to allow you to pull wire later. You'd want to run from your circuit breaker panel to the hot tub area. with 3 wires plus ground so you could do either or both 120 or 240V at your tub. Your electrician can probably best advise you on this.

Thanks, everyone! So it seems the best thing to do here is figure out what we're going to end up with (as far as the service panel goes) and see about having a conduit installed now, so we can run the wires later. Exactly what I needed to know :)