There's a local sew & vac shop that rents time, but even that gets expensive. You have to take 3-4 'certification' classes before you can use the machine, and they never let you use it on your own; when you're renting time on the machine you're also "renting time" from a store employee. (And it's just one person, so she has to be available.) They charge $40/hr with a 3 hour minimum. So each quilt, if you can get it done in one 3 hour session, costs you $120 to quilt. Ouch!
Certainly much, much cheaper than buying your own LA machine, but not inexpensive. I have managed to FMQ a king-size quilt on my domestic machine so at this point I haven't been motivated to rent any long arm time.
I did get to PLAY with that machine during a break in a class they were teaching, and I thought it was a lot of fun and I think I could get pretty good at it. But at $120 a whack....I could buy a lot of nice fabric for $120!