Rondomusic sells some Agiles that are Fretless, besides that, most of the sold
fretless guitars are custom shop guitars, Vigier sells one or two different models
but these are pretty expensive (handbuilt in France).
Godin sells a fretless acoustic guitar, nylon stringed afaik.
But believe me, the idea sounds pretty cool, but it's really tough to play fretless
on a guitar, even more than on a bass.
You have to touch the strings exactly on the right point, especially for chords or
it will sound really, really out of tune, that part is pretty tough on a fretless bass
and due to the longer neck you don't have to be as spot on as on a guitar, it's still
tough.
If you come from a classical background, played violin or something like that it won't
be as hard probably, but after getting used to frets and playing a pretty chord based
instrument like guitar it may be really hard to adapt to the fretless concept.
These are the only two avaiable Agiles atm:
http://www.rondomusic.com/al3110hsbffretless.html
http://www.rondomusic.com/st625eb3tsfretless.html
If you got a cheap guitar around, you could actually defret it by yourself, did this to
a bass (and once on the bass of a friend) it's not that hard, but I wouldn't try it on
a expensive guitar.
You have to heat the frets (with a soldering iron for example - touch ONLY the frets
with it, just for 5-10 seconds) and than pull them out really slow with pincers.
After you've done that, sand the fretboard a little bit, put some wood glue into the
fretslots (you don't need much, just a tiny bit) and press some veneer in there.
Move on to the next fret, after you've done that, there's a lot of veneer you have to
cut off (from the top and the side of the fretboard), just use a sharp cutter and be
precise.
In the next step, sand the fretboard again so everyting feels consistent (don't sand
too much, just a bit with fine sandpaper) and oil the fretboard.
That's it actually, you've just defretted a guitar neck and got a fretless guitar.
WARNING: I would only do this to a guitar with a bolt on neck that wasn't expensive
and that you don't love!
Remove the strings, remove the neck, let the neck rest for 1-2 days, do the stuff I
wrote above, let the neck rest for 1-2 days, put it back on, put strings on it.