contact her by e-mail again.  BTW, the assumption is that you put the necessary information in your first e-mail (day & time you want to see her, length of date, information for her to screen you, etc.).  If not, you may never hear from her.

Take a look at her website and make sure that your email to her followed all of her instructions. If you seem like a time-waster she might not write back to you. Did you introduce yourself properly? Did you refrain from mentioning anything illegal?
Did you give her all of the information that she requests for her screening? Did you tell her the time and day that you wanted to meet? Did you check her calendar to make sure she is not on vacation right now?
If you did all of these things then she probably will write back in a few days. If not then you better follow up right away with an apology and fix it.