Get Involved in Lunar Exploration!! - Pierre-Damien at the X PRIZE Foundation Launch Pad - This covers a number of ways people who aren't aerospace engineers can get involved, including the GLXP and many others.
Update (evening):
Student Lunar Projects - William (with Mike Fabio commenting) - Will and Mike add to the discussion, with Will showing this important quote from the "Building a Better NASA Workforce: Meeting the Workforce Needs for the National Vision for Space Exploration." report:
... These experiences should include significant numbers of opportunities to participate in all aspects of suborbital and Explorer-class flight programs and in research fellowships and co-op student assignments. ...
Recommendation 6: Support involvement in suborbital programs and nontraditional approaches to developing skills. The committee recommends that NASA increase its investment in proven programs such as sounding rocket launches, aircraft-based research, and high-altitude balloon campaigns, which provide ample opportunities for hands-on flight development experience at a relatively low cost of failure. ... In addition, NASA should take advantage of nontraditional institutions and approaches both to inspire and to train potential future employees. Investment in programs such as Centennial Challenge prizes and other innovative methods has the potential to pay benefits many times greater than their cost, by simultaneously increasing NASA’s public visibility, training a new generation of workers, and pushing the technology envelope.