Tf roslaunch issue, Package Path not set up properly?

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I've been trying to launch the learning_tf package from the tf tutorials, and seem unable to find it, no matter how much I change my env variables. The command is "roslaunch learning_tf start_demo.launch" but it's also failing on other commands.

The workspace I'm using is ~/catkin_ws/src I'm operating on groovy.

I'm convinced that the problem has to do with what I should set my ROS_PACKAGE_PATH to, but I don't know what it should be. I've tried several different options, and can normally locate things in /opt/ros/groovy/stacks, but not packages in catkin_ws.