I always wondered how the bd calendars were made, and which one to use based on where you are in the world. I'm still not quite sure, but through my novice bd research, I've found a great way to make your own calendar. If you have an understanding of such concepts as ascending/descending, moon phases & quarters, nodes, zodiacs, elements, etc, then when combined with this free application (Stellarium), you can basically create your own location specific calendar. I say location-specific because the application allows you to plug in your coordinates, and from that reference point, you can view a real-time 3D image of the sky. You can speed up or reverse time, see all of the stars, constellations, planets, and nebulas, and even watch the sun and moon traverse the zodiac in fast forward. This application allows you to see when the moon crosses the ecliptic (the node days) which also tells you when the moon is ascending and descending. It's really an outstanding program and I'm only just learning about it. Cosmic events, like oppositions and conjunctions are a little less obvious with the program, but it can be done.
It might not be as refined as a bd calendar you can purchase, and it might take a lot of time to write out your own calendar on Excel for example, but when you're farming/gardening somewhere outside of where the mainstream calendars cover, it's a great way to develop a better understanding of how and why the calendars work. I plan to use my own Taiwan-specific version of a biodynamic planting calendar in 2013.
To skip a lot of trouble, you can always check out this online moon calendar or just buy the most suiting one for your location; it's not as if they are expensive, but again, playing with Stellarium and jotting down notes in your bd journal is going to stimulate your connection to the land and skies.