Well, no one has taken a stab at this yet, so here's a temporary stopgap.
1) Anywhere besides whitegrass offer lessons in tele skiing for beginners?
There are quite a few PSIA Nordic instructors at other resorts; offering lessons for beginners however tends to presume gear availability and I don't know any local resorts where you could rent "beginnner" gear. There are demo shops, but that isn't what you seek. There have been a few threads on Telepalooza here, that could be a good place to start (and, really, a community to join).
To XC, DEFINITELY. It's really just an elegant shuffling, at least until you get into the fine points of skating.
I've posted this link before, warning, I have no idea how long it will stay current:http://www.patc.us/chapters/ski/
There is a ski fair Nov. 3 where folks sign up for trips:http://www.patc.us/chapters/ski/news.htm
To telemark, hmmm, possibly but not advisable. It takes an instructor whom you trust to cut down the sweaty work of the learning curve, to show that maybe the reason it isn't working is maybe you're just not going fast enough, and to avoid bad t habits forming from the good alpine ones.
3) How tele skiing affects your alpine skiing technique?
Don't worry about it. The reverse is far more likely.