Simply log on to Google Wave and type "wave.net open source project with:public" and add yourself to the wave.

Hey guys! The project looks awesome, and I'm interested in helping out, but I can't seem to find the group's wave. It keeps returning an error that there were no results for the search.

https://wave.google.com/wave/#restored:wave:googlewave.com!w%252BabyLUQl0D