Most email accounts have some disk storage provided as well. Mine has 10 MBy per mailbox. Use an FTP program (File Transfer Protocol) to move your PDF file from your PC to the disk at your service providers site. Then provide the URL to your subscribers in an email and they can just click on it.

Your ISP should provide an FTP facility for uploading, or you can get a free program like WSFTP from the web. It's very easy to use, and my choice for uploading eBay auction scans to my disk space.