Hiding Email

I'm searching of a way to send an email, and i don't want the user to know
where he send the email.

Let say i want to send a message to Bob001.
I will type Bob001 in the SendTo field.
When i type the Send Email button, i would like the web page to do this:
Get the username, Bob001.
Find his email in my database
Get the message in Message.
Create the email.
Send the email.

I don't want the user to be able to read the user email.

Every example show something like a "<a href" method. Which is not what i
need.

Is there a way to do so?
1- I don't own the web server
2- Windows 2000
3- Asp install (Asp.net too)
4- Php is not available (so no mail object)