Elton John, a longtime crusader in the fight against the global AIDS epidemic , announced yesterday that he was forming a foundation designed to fund AIDS organizations in the U.S.The nonprofit Elton John AIDS Foundation will be directed by John and based in Atlanta, where he recently bought a home. The foundation will concentrate on AIDS education, patient care and research, his publicist, Sarah McMullen, said in announcing formation of the foundation. John has long been active in the AIDS battle. The British entertainer recently announced that proceeds from all his single record sales in America, beginning with “The Last Song,” will be donated to AIDS organizations. “The Last Song” is about a young man dying of AIDS who is able to make peace with his father. John and songwriting partner Bernie Taupin recently pacted with Warner/Chappell music for administration of their post 1974 catalog in what was termed the largest deal of its kind.