Setting up your own host to work with SparkleShare is relatively easy. We've written a short page about it. The documentation should handle most of your questions.
If you can't set up your own host, you can always register a free account at Github or Gitorious.
Need more help? Join us in our IRC channel: #sparkleshare on irc.gnome.org.
SparkleShare is Free and Open Source software and is built by people who care about privacy and freedom. Not only can you use it however you like, you are also free to modify and redistribute it when you give the recipients the same freedoms.
If you'd like to help out: check out the wiki, roadmap, and source code. You can also report problems, write translations, or test development versions.