I felt the need to propagate to the interwebs a good resource I found today for setting up SSH to a guest OS using a host-only network:
http://muffinresearch.co.uk/archives/2010/02/08/howto-ssh-into-virtualbox-3-linux-guests/
I am running VirtualBox 4.1.4, but the blog entry is still quite relevant. The only difference is how to set up a host-only network. In the VirtualBox Virtual Machine Manager, under menu option File choose Preferences. Click the “Network” tab in the window that follows, and then you will see an interface for adding host-only network adapters.
The default network address is still 192.168.56.1, so the everything after that is applicable.