It's certianly not perfect, but here's a calendar of Buddhist holidays/observances that I ganked from a few different sites and then modified. Most of the observances are Tibetan, but there are also the big three Zen days (Buddha's birth, enlightenment, and death) because I like to celebrate those things outside of Vesak, and then there are a few days relating to Kuan Shih Yin because I have a love and respect for her as another embodiment of Chenrezig/Tara. I know, I know. I'm such a Salad Bar Buddhist.
There are a number of things not included, I know, such as auspicious days, prayer flag days, moons, certain pujas, etc. If there is anyone on my f-list (looooong shot here) that knows anything about the Tibetan Calendar, and knows that I've missed something BIG (are there more days for the Medicine Buddha or Chenrezig, or more Sojong Days, for example?) then feel free to let me know. It feels a little bit incomplete.
Anyway, onto the calendar!
* 1/22: Amitabha Buddha Day
* 2/5: Sojong Day (Tibetan Buddhist day of fasting, confession, and reparation for harm done)
* 2/6: Shakyamuni Buddha Day
* 2/7 to 2/21: Losar (Tibetan Buddhist New Year)
* 2/14: Tara Puja
* 2/15: Nirvana Day
* 2/21: Amitabha Buddha Day
* 3/7: Shakyamuni Buddha Day
* 3/15: Tara Puja
* 3/21: Amitabha Buddha Day
* 3/26: Kuan Yin's Birthday
* 4/6: Shakyamuni Buddha Day
* 4/8: Buddha's Birthday
* 4/13: Day for meditation on Avalokitesvara and Green Tara
* 4/20: Amitabha Buddha Day
* 5/5: Shakyamuni Buddha Day
* 5/12: Tara Puja
* 5/19 Vesak (Tibetan celebration of Buddha's Birth, Enlightenment, and Death)
* 5/19: Amitabha Buddha Day
* 6/3: Shakyamuni Buddha Day
* 6/11: Tara Puja
* 6/18: Amitabha Buddha Day
* 7/3: Shakyamuni Buddha Day
* 7/6: Celebration of Buddha's first Teaching
* 7/6: H.H. The Dalai Lama's Birthday
* 7/10: Tara Puja
* 7/18: Amitabha Buddha Day
* 8/1: Shakyamuni Buddha Day
* 8/9: Tara Puja
* 8/16: Amitabha Buddha Day
* 8/30: Shakyamuni Buddha Day
* 9/7: Day for meditation on Gold Tara (provider of all sustenance and necessities)
* 9/15: Amitabha Buddha Day
* 9/29: Shakyamuni Buddha Day
* 10/7: Tara Puja
* 10/14: Amitabha Buddha Day
* 10/17: Celebration of Kuan Yin's attainment of Bodhisattvahood
* 10/21: Lha Bab Duchen (Tibetan Buddhists celebrate the Buddha's descent from heaven after teaching the Dharma there)
* 10/28: Shakyamuni Buddha Day
* 11/6: Day for meditation on White Tara
* 11/13: Amitabha Buddha Day
* 11/22: Day for meditation on Manjusri and Prajna-Paramita
* 11/27: Shakyamuni Buddha Day
* 12/5: Day for meditation on Red Tara (protector against evil and harm)
* 12/8: Bodhi Day
* 12/12: Amitabha Buddha Day
* 12/27: Shakyamuni Buddha Day