Kyle Hailey has started putting together a much needed Oracle wait event reference.
You can access it here.
By the way, Oracle documentation also has a wait event reference section, it has more events, but it’s less detailed…
NB! After a 1.5 year break, this year’s only Advanced Oracle Troubleshooting training class (updated with Oracle 12c content) takes place on 16-20 November & 14-18 December 2015, so sign up now if you plan to attend this year!