How to get from Ha Noi to Ha Long?

Hello all,
I plan my trip beginning (start point Ha Noi, end point - HCMC) and of course want to visit Ha Long bay. But I don't like to take excursions with big group.
As far as I understand, there is possible to hire junk boat (may be with 3-5 companions)right in Ha Long.
But I can't find information how can I get from Ha Noi to Ha Long. Regular bus? Train?
Any suggestions are welcome.

hi
From hanoi to halong, you can take the bus to Halong in the Gia Lam parking or go to sinh cafe to buy bus ticket to Halong 2ways(no tour).

thanx a lot!