I have a Torker Unistar with a 20" wheel and that's been perfect to learn on. Depending on your height, the seatpost usually comes pretty long, so you may have to cut it down with a hacksaw to get some flexibility on seat level.
As far as learning, I kept a little logbook of each time I went out. It honestly feels impossible at first (constantly falling in 360 degrees), but you just have to keep working on it. I did most of my learning at a school playground (lots of space to wobble around) and leaned against the school wall for support.
I practiced with mine in office space. 1 hour of coding, 5 minutes of unicycling and so forth. I just tracked along a wall, forth and back, forth and back until I didn't need the wall
Yow, the electric unicycle cited in the article is over $600! The Torker is $90.
Maybe it's possible to build an electric one cheaply? I wonder how much tlb's cost...
EDIT: http://tlb.org/#eunicycle "All together the components, in single unit retail quantities, cost about $1500." I wonder how expensive it would be today?
As far as learning, I kept a little logbook of each time I went out. It honestly feels impossible at first (constantly falling in 360 degrees), but you just have to keep working on it. I did most of my learning at a school playground (lots of space to wobble around) and leaned against the school wall for support.