I wanted to publish a PDF document online. But I do not know any websites that publishes it for free.
There are tons of ways to do it. I suggest using Scribd.com. You can make it private or public, give certain people access if they have the access key, and they will be able to read and download it too.
Scribd is a good choice. Also GoogleDocs, maybe BuzzWords (by Adobe) or possibly Office Live webapps.
Depending on the topic of your PDF document, you can choose to host it on a file sharing site and spread the word around on discussion boards. DocStoc is an option that's not covered by the above link. You can also look through Calameo.
please have a look at this article: 3 Websites To Publish & Share Your PDFs Online