I transitioned from Power to Gliders (then later on went and got my
Commercial rating). My club isn't very well-organized so I wound up
going to a couple of commercial operations for those ratings. I've
also visited a few since then (for contests and such). Many of the
good commercial operators in the western US are going to be beastly-
hot in August; but I'd recommend the following (in no particular
order):
Williams Soaring (central California, about 2-3 hours' drive inland
from San Francisco, CA)
Estrella (about 30-45 minutes south of Phoenix, AZ)
Sky Sailing (about 1-1.5 hours east of San Diego, CA)

Williams is probably the largest and is run by the Mayes family
(husband, wife, and teenage sons are all hard-workers and have a good
staff). Its not the cheapest place to get your license; but they
arguably have better equipment than the others. I haven't flown _at_
Williams; but the Mayes family ran the National Championships that
just finished last week and I was mightily impressed with their skill,
organization, and generosity of spirit.

Estrella is run by Jason Stephens and a small crew of very capable
folks. Jason is a multi-time aerobatic champion in gliders and has a
lot of enthusiasm for the sport. I had a good down time there,
finishing up my commercial glider ticket.

Sky Sailing is where I got my private glider rating after making the
switch from power. Its a somewhat-isolated desert valley location
with a pace and a feeling all its own. But the Willat family are
accomplished glider pilots who teach well.

One word of caution: Training to fly gliders is *not* the same as
soaring! You may be surprised to see some of rudimentary trainers and
short flights that make up the training regimen. Sadly, soaring is a
skill that takes a bit of time and effort to build up to. But it is
WELL worth the time and effort, as long as you stick with it!

Best of luck, and feel free to post here if you have more questions!

Take care,

--Noel