Best way to get a file's path and paste it in a text file

Best way to get a file's path and paste it in a text file

I am trying to write a program, or HTML page actually, to get a file's
path, then open a New E-mail in Microsoft Outlook (or the default e-mail
program the user uses) and paste the link in the new message.
The program will have 3 inputs, Firstname, Lastname, and Date, and a OK
button. It should look for the file with those three inputs as a file name
(ie.: John_Smith_22AUG13.pdf) and get the path to paste it in the email.
Now I am good at programming in javascript, but I'm sure this is not the
best way to do something like this, or even if it's possible.
I was wondering if someone has done something similar in the past and has
any advice or programming language I should use to do this. I would like
this to be a webpage like HTML but will be used internally so security is
not really an issue.
Anything helps! Thanks!