My new ZJ did not come with power seats unfortunately.
The problem I am having is that I am so tall I keep hitting my head on the ceiling and it's kind of irritating. Is it possible to take a power seat from another ZJ and put it in mine? Yes I am pretty with electrical so that is not a question.

 

Very possible. The seat plug may even be there already. If not, all you need is a power and ground.

 

My '02 WJ has a power driver's seat, but a manual passenger's seat... I also want to add a power seat on the passenger's side.

The wiring harness may be hidden under the carpet, so you'll have to pull up the carpet in the front and see if there's a wiring harness that's not hooked up to anything near the seat and plug it into the new seat you get to see if it works. Much like there's sometimes speaker wiring in the rear headliner of a 1997-2001 XJ Cherokee to add rear speakers if your Jeep didn't come with them, it's sometimes just all there.

If you don't have that harness, much like Bustedback suggested, you just have to find a power source to tap into and a ground connection.

 

I've been told the wiring is under the console near the storage compartment/armrest. I know that's where the seatbelt switch connector is.

 

That's good to know. Just wish I could find a good parts vehicle.....

 

Incidentally, the cigarette lighter is a good power source. It's easy to access and fused 20 amps. It's also accessory wired so it turns off with the key. The other power plug is constant hot and fused separately. I used the cigarette lighter feed to power the relay signal input on my aftermarket fog lights so I don't forget and leave them on.