Retrieving a user object from AD

 Hello,
 I'm working on a password reset app and I'm very new to ASP... actually, this is the first ASP app I've ever built. Anyhow, from what I've read, I have to impersonate an admin user, then grab the specified user object and reset their password. Thus far, I've got the impersonation part done and working. My first question is: How do I load a specific user object based on email address, and secondly, how can I reset their password (do note that I do not have their current password, hence password reset)? All of this code would be running in a .aspx page.
 
Any and all help is appreciated!!!
Thanks,
 - Jeff Miller 

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