Here is another trumpet trio I did not immediately think about (see my previous message on Roy Campbell) : Trio East, with Rich Thomson on drums, Jeff Campbell on bass and Clay Jenkins on trumpet. It's not really free jazz, yet very adventurous jazz. Two of their CDs are available on iTunes (Best Bets since January 1 of this year, Stop-Start since last year : check under Rich Thompson and/or Jeff Campbell. Stop-Start is really worth having. Three top musicians.