This is more or less what I sent to Punha. I have run two groups for Queer youth: one (BGLAM - Bisexuals, Gays, and Lesbians at Marianopolis) was at my cégep (junior college); another (Haven) was an independent, irregular social club that organized activities and outings and whatnot.
At any rate, as for your group. Identifying staffers would be a good thing to do. I know that one of the counsellors at my cegep was invaluable when I was running the group. Are there student counsellors at your college? What if you went from each to each, sounding them on their awareness of Queer issues and their willingness to help support a Queer group? Staff support can be invaluable.
As for publicity, I would guess the thing to do to put the word out would be to put up flyers and possibly run an ad in whatever paper or news bulletin they have there. Be explicit, but not too in your face (“Questioning your sexuality? We’re starting up a Gay-Straight Alliance, contact littlegaygroup@hotmail.com” or whatever). And put them everywhere - someone might not feel comfortable staring at one long enough to read the address,
but if they pass twenty on their way to class they’ll get the message. Be prepared to put up LOTS - they WILL be torn down, occupational hazard… :-/ If you keep putting them up, eventually people will get tired and go back to cow-tipping or whatever. It does work.
Physical violence is a risk, and it’s one you’ll have to decide whether or not to chance. Some situations are simply not worth the danger; you will have to decide that for yourself. I would advocate sticking to well-trafficked hours and areas (practical anyway, if you want people to see your flyers 
– don’t be caught alone. If you accrete some allies, especially staff ones, try bringing them with you for safety’s sake.
If you expect static from the administration, make sure you know the relevant code inside and out. That will show them that you’re not to be fucked with. This is a general attitude to have anyway 
The whole point - right now, Queer people are invisible at your school. The goal is to make Queerness visible. That will make people less afraid and more willing to stand up for themselves. It’s kind of a chicken and the egg problem, but one that’s relatively easy to break into.
As for meetings themselves? In the beginning, you might try meeting prospective, individual new members on a comfortable, one-on-one basis. Is there a café or lounge or some other anonymous locale where you can meet them? A neutral environment where they might expect to be in a crowd that doesn’t know them - so they can feel safe in having others around without feeling UNsafe for the same reason? (When Nicole and I were running TeenHaven, we used to meet people at the mall.)
When talking with them, just be reassuring. If they’re not out, it’ll
probably be enough of a struggle to make it to the meeting, if they even do. Just introduce yourself, chat, find out a little about them in a casual way, and tell them what you hope for in the group. Let them lead the conversation.
Once you’ve got one or two members who have met you and are comfortable with you, you’re ready to have a meeting! For the present I’d advise keeping the meeting time a secret among the members rather than publicizing it.
When the group is running, even if others don’t care to, you might want to talk to campus press, just to get the word out more.
These are all just suggestions of course; it’s essential you do only what you feel comfortable with - a scared, burned out facilitator is no good to anyone, so keep your reserves and don’t overexert yourself physically, mentally, morally, or emotionally.
I hope this makes some kind of sense.