John Sirois (email@example.com)
William Farner (firstname.lastname@example.org)
You can browse API docs here.
Artifacts are published to the public twitter maven repo at http://maven.twttr.com. To find out which artifact contains the classes you'd like to use, you can just navigate to the API docs for the class you're interested in. Its artifact info will appear along the top of the page. For example you can find out the artifact com.twitter.common.thrift.ThriftFactory is exported in.
You can also clone the project with Git by running:
$ git clone git://github.com/twitter/commons