JOEL OBERSTEIN, the president of Almighty Music Marketing and a familiar figure in the sales and retail world, died Friday. He was 50. Oberstein succumbed to West Nile virus, which he contracted after his immune system was lowered by treatments for MS. He began his career at the L.A.-area based Tempo Records chain, where he eventually rose to the title of GM. While at Tempo, he worked with future major A&R label execs Todd Sullivan and Benjie Gordon, and Alice in Chains bassist Mike Inez, who said, "Joel was the shit." After stints at Atlantic and Right Between the Acts, Oberstein joined forces with Internet entrepreneur Clark Benson to form Almighty/Isis, which launched the Almighty Retail Database and the New Releases Now website. Despite working with onetime HITS losers Mark Gracious and Anna Willard, Oberstein became one of the most beloved execs in the business, bridging the gap between indie retail and the labels. Almighty will continue to operate under VP Vince Hans. Oberstein is survived by his wife, Melissa, and daughter, Sophie. Donations in his honor can be made to the MS general research fund at USC’s Keck School of Medicine. (11/6a)