R&B singer/producer Ne-Yo celebrated turning 30 this week at several Manhattan hot spots. On Tuesday, he was spotted at club Greenhouse in SoHo, where he hopped in the DJ booth and sang a few songs from his new album, “R.E.D.” The next night, Ne-Yo and 35 friends — including Tyson Beckford, Estelle and Fabolous — had dinner at Acme in NoHo. They then headed for a quick stop at Mister H, where singer Brandy celebrated her new album, and then to Meatpacking District lounge SL.