Here are some links to a number of masterclasses that are on youtube.
Greg Abate
http://youtube.com/watch?v=Ky1fusRijX4&feature=related
http://youtube.com/watch?v=T8_CSbF8LT0
http://youtube.com/watch?v=-hirmi_eEwo
Michael Brecker
http://youtube.com/watch?v=5mLDdxEhRnM
http://youtube.com/watch?v=hfgfo1cj_BQ
Dave Liebman
http://youtube.com/watch?v=yeSCrDyxMkg
http://youtube.com/watch?v=_YtFMZ93tV4
Joe Lovano
http://youtube.com/watch?v=O_ZRLr_ijcI&feature=related
http://youtube.com/watch?v=a8-9DhC0ehY
Lenny Pickett
http://youtube.com/watch?v=zZhHU065C6Y
http://youtube.com/watch?v=_6aHkN9jnNk&feature=related
http://youtube.com/watch?v=6n5SK9kHaMY&feature=related
Sonny Rollins
http://youtube.com/watch?v=oImECanKC0k
George Shelby
http://youtube.com/watch?v=uIIIGzWODdE
http://youtube.com/watch?v=Jp9XZteOMZc
http://youtube.com/watch?v=5aVF6iQoQ9w
http://youtube.com/watch?v=Opu6WWAvb0M
Ernie Watts
http://youtube.com/watch?v=-UOGGlHOvP0
http://youtube.com/watch?v=LGH18cB0Iz4
http://youtube.com/watch?v=zg6gMS5oXbE
Grover Washington Jr.
http://youtube.com/watch?v=tZJR8MqB67g
http://youtube.com/watch?v=PhG8DXZAY14
Greg Abate
http://youtube.com/watch?v=Ky1fusRijX4&feature=related
http://youtube.com/watch?v=T8_CSbF8LT0
http://youtube.com/watch?v=-hirmi_eEwo
Michael Brecker
http://youtube.com/watch?v=5mLDdxEhRnM
http://youtube.com/watch?v=hfgfo1cj_BQ
Dave Liebman
http://youtube.com/watch?v=yeSCrDyxMkg
http://youtube.com/watch?v=_YtFMZ93tV4
Joe Lovano
http://youtube.com/watch?v=O_ZRLr_ijcI&feature=related
http://youtube.com/watch?v=a8-9DhC0ehY
Lenny Pickett
http://youtube.com/watch?v=zZhHU065C6Y
http://youtube.com/watch?v=_6aHkN9jnNk&feature=related
http://youtube.com/watch?v=6n5SK9kHaMY&feature=related
Sonny Rollins
http://youtube.com/watch?v=oImECanKC0k
George Shelby
http://youtube.com/watch?v=uIIIGzWODdE
http://youtube.com/watch?v=Jp9XZteOMZc
http://youtube.com/watch?v=5aVF6iQoQ9w
http://youtube.com/watch?v=Opu6WWAvb0M
Ernie Watts
http://youtube.com/watch?v=-UOGGlHOvP0
http://youtube.com/watch?v=LGH18cB0Iz4
http://youtube.com/watch?v=zg6gMS5oXbE
Grover Washington Jr.
http://youtube.com/watch?v=tZJR8MqB67g
http://youtube.com/watch?v=PhG8DXZAY14