First of all, Taiga is very big thing, so address in the Taiga isn't much helpful for you :)
Secondary, my apologies about some information is only in Russian, especially maps.
The Curch of the Last Testament has their village in the Krasnoyarsk Krai. Their site is very old, and the only thing working there is the main page. Also they have international website, and there is the location of them.
Official postal address is:
662925, Krasnoyarsk Krai, Kuraginsky District, d. Petropavlovka, ul. Kolhoznaya, d. 9.
Please note that Tiberkul is named after lake Tiberkul, which is situated in 130 kilometers from Kuragino (district center) and in 30 kilometers from Cheremshanka village.
Other villages near the lake are: Tagasuk, Zharovsk, Gulyaevka.
According this and this, the roads to the lake is available ONLY IN WINTER - on snow (from Gulyaevka and Cheremshanka). In other time, you can get there only by two methods:
- local citizens's tankets and tractors :)
Also here is some information about some club in Abakan, which regulary goes to the lake on their off-roaders, but this is quite uncertain.