Taipei travel agent for Trans-Mongolian Rail tickets?

Hi. Has anyone ever booked or inquired about Trans-Mongolian (Trans-Siberian) Railway tickets with a Taipei travel agent? It seems to be a complicated procedure, and I’d like to have it all (or mostly) arranged before I head out of here. Any info is appreciated!

Do you have to book through a Taiwan agent? Why not use some other agent and have them mail the ticket (with tracking number) to Taiwan. I am afraid no one in Taiwan goes that route so no one sells it. Why not Google it (in Chinese) on Taiwan Google, or Taiwan Yahoo, or maybe book though a Beijing travel agent and pick it up when you get there.