You can find additional information about various aspects of Tibetan Buddhism on these sites.
- Dharma Sun - Online Tibetan Buddhist Teachings & Resources
https://dharmasun.org/ - Rangjung Yeshe Study and Practice Group - East
http://www.rygroupeast.org/ - Shedrub Development Fund
http://shedrubfund.org/ - Riwoche Tibetan Buddhist Temple
http://www.riwoche.com/ - Tibetan Buddhist Resource Center
https://www.tbrc.org/ - Thubten Phuntsog Gephel Ling (Portugal)
http://www.gephelling.org/ - The Hermitage of the Awakened Heart (Scotland)
http://www.hermitageoftheawakenedheart.org/home