The Jazz Society of Santa Cruz County has a lot of great thing happening every month.
Jam Sessions: They hosts a 4 hour jam session every Sunday from 3.30-7.30 pm at Bocci's Cellar (140 Encinal St. Santa Cruz.) House band 3.30-4 Open jam 4-6.30 Invitational jam 6.30-7.30 Adm. Free, Full bar, special $8 meals, dance floor. Friendly, supportive, non-competitive atmosphere.
Jazz Workshops: Every Tuesday from 7.30-9.30 pm West Side Santa Cruz Play/sing jazz standards in friendly workshop. All levels. Requires ability to play an instrument, and preferably read lead sheets. More info call 831 427 2792
They also produce an annual compilation CD with tracks by the many local jazz groups in our area. Check out their website for all things Jazz in Santa Cruz http://www.santacruzjazz.org/index.php