I think we need a two prong approach to the PSA.
We need a big gun, well known, ESPECIALLY amongst younger people to do a statewide PSA that all stakeholders can disseminate. The suggestion of Lance Armstrong is a good one. He's recognizable across generations, has plenty of hero cred and he has a health connection, that of being a cancer survivor. Beyonce Knowles is another great idea. I wouldn't know her music if it was playing in my office right now, but I know who she is, that she is a famous singer, and has been in a couple of movies, (and I'm a geezer who doesn't watch TV). The main thing is getting someone that people, especially young people, will relate to and believe in the message.
We need to get local people in local markets to do the same thing. Not the mayor, or a local congressman, but someone trusted by average people. Local sports heroes, famous characters of the locale, even popular TV personalities like weathermen, talk show hosts, and ministers.