So you meet this girl in class (or work) you get to talking, maybe you ask her for lunch.  It goes well and you think you might see her again.  At this point you only have her email address and maybe next time you can get her number, but at this point, why.?  Are you calling to call her to chit chat?  Maybe for to text, but don't start calling her. 

And in the meantime (while you are waiting to set up a second rendezvous) don't Facebook her, don't tweet her, don't send her a Myspace message...doing all of that crap just puts you in with the rest of the lumps.  Keep it special and keep it brief.  Just because there are a 1000 ways to get in touch with her, doesn't mean you have to.  Be different, be a bit more elusive,  But more importantly don't be like everyone else. 

The point of getting to know someone is, getting to know someone.  If you jump on Facebook right away, you see it all.  Which in some instances maybe isn't a bad thing, it may give you something to talk about.  But hold off.  Sure, check out her profile, do a bit of research, but don't start sending her 'friend' requests...stalker.