There are several options, which I'm sure are explored from jmatt's links above. My preference is to add the archive PST to your list of folders when you open Outlook:
Under Tools -> Services, you'll find that you can add a "personal folder". It'll prompt you to browse to the PST (select the archive.pst), then you can give any name you want to the entry. Afterwards, it'll show as an active entry in your Folder List.
~cdogg
"The secret to creativity is knowing how to hide your sources."
- A. Einstein