f/f, the first thing you need to do is ask yourself if this is something you really want to get into. If not, be up front about it. But, if you care enough to give it a shot, then, tact's advice seems sound.
There is also a book entitled SM-101 that is excellent in explaining things. If you can find folks nearby who are into the whole BDSM scene, you can probably get sound advice from them. The vast majority of those I've met are open to helping out newbies by explanation, demonstration and just generally helping them feel more comfortable with things.
Whatever you do, I'd take things as they come. Remember, there's even more variety in the BDSM scene than in the tickle scene. So, if one thing turns you off, there may still be other things you can try. If you ask this gal what she has tried and enjoyed and (safely) start from there, that would be a good start. Even if there are only a few things you can both enjoy together at this point, that's cool. Remember, though pain turns most people off, there ARE some who enjoy it...and can get aroused from it. So, keep that in mind to help you get past the "I don't want to hurt you." feelings that will likely arise. As long as you know what you're doing and follow safety, you're not likely to hurt her.
Side note: There's a special running on the sundance channel (if you get that) called "Whipped". It discusses the whole scene from the perspective of a few of those involved in it. They actually did a pretty good job on it. So, if you want a taste of the mindset, etc. it's something you may want to check out.
Ann
