Don't get too excited - I don't code well and just started messing around with this.
So as to not start from scratch, I utilize the excellent SonosPy extensions developed by Mark Henkelis. You can find the open source here on github: https://github.com/henkelis/sonospy/wiki/Welcome-to-Sonospy.
Configuration for the plugin is simple - simply enter the ip address or dns resolvable hostname of the server running the SonosPy extension as well as the tcp socket accepting connections. The default in the package is 50101. When creating the device, the only configurable item is the name of the ZonePlayer.
I'll keep the plugin download page as current as possible with a package as I continue to build it out. The initial goal is to simply read current status of the controller. The Indigo plugin will poll the SonosPy server every second for an update of all ZonePlayers that are configured as devices.
Please post any issues or comments on the Indigo message boards and I will attend to them as quickly as possible. I've only put a couple of hours in to this, so it is very rough as indicated by the initial release version (0.1.0).
Link to download: https://vulture.lagaros.com/wiki/pages/a24599q3r/Sonos_ZonePlayer_Plugin.html