In Netscape, open a window to send a new message. Input the e-mail address it is addressed to, and under that, click on the paperclip. This will show a blank listing on the right hand side, click on the white area and it will pull up a listing of files. Find the file you want to send and click Open. This will add the filename in the listing. You may click on the white area again and select another file for multiple files. Then, type your message and send it! Your files will automatically be appended to the end of the e-mail.
In Outlook, go to a new message, put in your address to send to, your subject and your message. Click Attach at the top, select the file you want to attack and select Attach. You may do this multiple times for multiple files.