Below is the documentation available for V3 of the Shibboleth Identity Provider, including all 3.x patch and minor upgrade releases. Documentation is split up in to two parts: documentation meant for individuals that are deploying and managing an Identity Provider and documentation meant for individuals that are developing custom extensions for the Identity Provider.
The of the Identity Provider is V3.1.1, and the is V2.4.4. The official announcement on the staged EOL process for the V2 product can be found here, and security maintenance ends on July 31, 2016.
All software, including archived releases, is available from http://shibboleth.net/downloads/identity-provider/ and each release is accompanied by a detached PGP signature using one of the keys listed in the project's PGP_KEYS file.