Interested in one of those prestigious Presidential Management Fellowships? A newly  launched web site hopes to answer all your questions about the selective program, which offers recent graduate students a paid, two-year stint with a federal agency, followed by the chance for a permanent career. The interactive site is backed by the Robertson Foundation for Government, a nonprofit group that seeks to attract top grad students to federal careers in the foreign policy and national security arenas, and the online social network, GovLoop. The new site offers considerably more material than is available from the official site, including tips and…