For samples, documentation, and usage information, please see http://ehcache.org.
We released 3.1.1 on July 18th 2016.
The release notes contain the links to the artifacts and the documentation to help you get started.
You should consider upgrading to 3.1.x as it does all 3.0.x does and more with a fully compatible API. The only thing to note is that transactional support has been moved to a separate jar.
We are now working on the missing features of the clustering tier of Ehcache 3 which will be included in upcoming 3.1.x releases. We may still do a last 3.0.x release to include all fixes that have been made on it, but this is now less a priority.
See the milestones on GitHub for more details on the current status.