Hello, planning to go Beijing, guangzhou, macau on mid september 2009

I want to ask, I would be arriving in TianJin Airport with a family of 4 to 6 person. To go to Beijing City (staying in hotel over there), how do i do that? Get a Taxi to TianJin Station to take a fast Train to Beijing and then switch to taxi to go hotel.. or Take a TAXI from TianJin to Beijing City? which is more cheaper?
1. How much is Train from TianJin to Beijing Cost?

Another Question, From Beijing, if i want to go to GuangZhou.. which is the cheaper Airline to fly there? How much is it cost?