Yes, the bus station is called ZOB! You can go by bus or train. I think it is much faster, when you catch the train at the ZOB! However, if you need detailed informations, feel free to write me a PM. I am not from Hamburg, but we have the same system here in Bremen (1h to Hamburg), too! I think I can translate a few things for you!
Here is a good website from Hamburg, about the ZOB system: Hamburg ZOB
--Sören