I think that before you do, take a moment and think about this - what is it that you like about her, why in this time in your life you decided to have a crash on someone you don't even know and who is in a relationship. I think that a lot of time, our emotions are giving us a lot of information about ourselves that we just choose to ignore because it seen unreasonable or unimportant.
I know that for a while I kept having crashes or falling in love with people that were either living in far away places or was unavaliable emotionally or were in other relationships. The reason, as it turned out was not that I had the amazing bad luck of finding lovely people who were difficult to get, but that I was very much in need of being in love but also very much not ready to make a commitment or be in a relationship.
I think that trying to get this girl "of your head" by distracting yourself, would not only not work (it's sort of like saying "don't think about pink crocodiles" - not that you were going to, but trying not to think about something basically get you to think about it) but trying to use this opertunity to examine your feelings ad yourself.
Again, most times when we fall in love it's not so much about the other person but about ourselves.
And if this doesn't work, there's always the method of drinking a lot of alcohol and singing in the street (hay, it works!)