What follows is not intended to be comprehensive:
some of those listed below do a far better job in this respect. First of all there's
a list of what I consider to be links directly related to free improvisation; this
is followed by a much briefer listing of more general jazz links.
Free improvisation links
Musicians
Avantart free and new music including Peter Kowald, Ned Rothenberg, Dror Feiler, Sergej Kuryokhin, Jim Meneses and Sainkho Namtchylak