This is an addendum to Jocelyn's advice, for once you get everything
you want where you want it in your pst. I have thousands of messages in
tons of folders and my pst was getting huge. IMake a new outlook file
and call it (for example) clientspre2006.pst. With both outlook.pst and
clientspre2006.pst open, drag all your client folders from outlook.pst
to clientspre2006.pst and then start new client folders in outlook.pst.
Same with any other major group of emails. I have one for the genealogy
program I use, for one specific client as well as the general client
one, and a couple other things. I've never had anything show up in
Archive folder (don't know why but suspect due to the way I have my
folders arranged). I don't care, because using my method works well for
me.

There is supposedly some way to compress/optimize the main pst to get
rid of the bloat, but I don't remember how and can't find it at the
moment.