You will have to copy your web directory (usually /web though that may have changed in more recent versions of the documentation), your AOLServer (/usr/local/aolserver) and PG (/usr/local/pgsql) and your init scripts (location depends on distribution).
If you haven't done any customisation or used the site yet then you are probably better off doing a clean installation on the new machine and taking note of where you install everything.
