You should look into Superior Drummer. The drums in GarageBand are ok, but when you hear the articulations that you can get with SD2, your jaw will drop. Mine did. I was using a Roland TD-6V for my sounds, it came with my electronic kit, and I was happy with that. But "The Mayor" on this forum Tom Roady introduced me to SD2 and the MacBook. My jaw dropped. I couldn't believe the realistic sounds I was getting. You can hear the snares buzz when you hit the toms. GarageBand drums would be a great starting point because investing in more software can get expensive. I played my TD-6V for about a year and it allowed me to get proficient on my ZX, and now with SD2, my playing has gone to another level.
I know there are a few other Zendrummers in California, not sure their exact location to LAX, but hopefully others will post their location. I started a new thread just for that. Feel free to ask any other questions, everyone on the forum is here to help.