Flash Tune for BA.... is it worth it ? and does anyone know someone in the Berwick (Vic) Area that does it ??

Yups do it,you'll need a flash box for mods down the track anyway.
Get a few things done first though.

Obviously the more mods you do before the tune the better the tune can get, but a tune on a completely stock engine can and will generate gains. Some prefer to just do a flash tune to a stock engine rather than get the usual intake/exhaust mods, since it helps with resale, and is harder for constable plod to spot, for roughly the same gain and less noise.

Depends on what you want to achieve overall.

If you plan on changing intake and exhuast do that before the tune.

If you just want a few more horses, and keep it stock, then a flashtune is a good way to free up power.

as for tuners, concentrate your search around the dandenong area and i think you will come up with a winner. Cant remember the name, but Im sure theres a dyno tuning place that Fordmods have used there for a dyno day before.