Hello Gaurav,
Assuming that the documents are not of critical nature and security is not really a big concern then, you can develop a handler in .NET to accomplish this. The handler will receive a simple parameter say document id as part of query string. The handler will then retrieve the document corresponding to this id and will stream it back to end user. Please have a look at
this[
^] article, it should you get started. I guess you already have figured out how to create a link and send it via e-mail.
Regards,