Hi Amanda.
Where will you be in the south of France ?
I know that our country is absolutely ridiculous compared to your continent, but the a journey by car from Perpignan to Nice could take about 4-5 hrs...
The best places for Diving are near Marseille, La Ciotat, Toulon, St Tropez/Frejus/Antibes/Cannes.
Places like Nice or Cavalaire are very nice, but for deep diving.
If you just have 2 dives to do, try to go near Toulon : Hyeres, and ask for a couple of dives near the Islands of Port-cros or Porquerolles.
There are also many very interesting wreks around, but most of them are too deep for you I guess.
I found few SSI dive op that I don't know myself :
http://www.destination-plongee.com/plongee.php or
http://www.bulles-passion-plongee.com/ email them. (The dive op I know is not a PADI-SSI one).
Near Marseille :
Plong? Passion Carry-le-Rouet a good place for easy diving. I know them, they are very nice and speak english.
The water temp could be quite low in April ( something like 12-14°C to 16 if you're lucky), don't know where you've dived in OZ but...
And oh : I'll be in Australia in 1 week ( NSW) :cool2:
BRING OUT THE SEALS THE WEEDY AND THE GREY NURSE SHARKS !!!!
YEEEEEEEEEEEEHAAAAA !!!