Limp Bizkit, DMX, Filter, Method Man, Redman and the Crystal Method have all signed on for the second annual Family Values Tour, which is set to launch on Sept. 21 in Pittsburgh. No D.C. date has been announced . . .

R&B loverman Usher has reportedly recorded a duet with Mariah Carey. Usher told MTV News that the track may appear on Carey's upcoming album, "Rainbow." Carey's album is tentatively due out in November . . .

Sting is doing a small venue tour to promote his new album and will play a D.C. date sometime in November. Ani DiFranco will also play a smaller-than-usual venue here: She will play the 9:30 club on Oct. 6 . . .

Tori Amos and Alanis Morissette are currently touring together, and Amos recently explained in part what bonds the two singer-songwriters: "Alanis knows what it's like to have left your underwear behind in the hotel room, and it wouldn't be so bad except that it was your Prada underwear that you bought with a royalty check and even that would be okay, but you already wore them. So, she understands what it's like to know that someone is hawking your dirty Prada underwear on the street."

CAPTION: Limp Bizkit is game for the Family Values Tour.