retrieve value

Question

I have a aspx page. I want to send mail along with attachment. But i dont want to hard code all the details. I want server to take value from the textbox and then send mail. Also i want the form to open the file open dialog box & search for the file and then send the selected file as attachment. I know how to do that in windows application. But am not able to do it web application. Please guide me how to it. Currently i have coded all the details like sender mail id, sender mail password, reciever mail id, subject, message, file path. I also have to type in the same thing when i run the application. I dont want to type twice. I want to type only when i run the application. Please guide me in doing that way.

Thanks in advance,

Avinash