So she gave u an e-mail and managed to identify you straight away ? that means she may have been waiting for ur mail.. or some manner of contact.
well, just e-mail saying that u like to be friends , go out etc etc. man.. e-mail is like phone.. just that u can write longer texts. Just make sure she is the chick in the bus stop...

just leave a mail.. good things takes time. Since its e-mail. U can e-mail her n focus on other girls. Its like win win situation for u.