Congrats on getting your learners!
A good resource for new riders is www.netrider.net.au
If you are in Melbourne I have had great experiences with Bikemart and Peter Stevens in Ringwood. Insurance is likely to be expensive...due to age and the type of bike you hae bought...there are an awful lot of CBR-250's that get binned and unfortunately insurance rates reflect this...you can try
Western QBE
Swann
Arista
Shannons
E Bike
Insure my ride
You may be better off with 3rd party if full comp is too exxy...however don't skimp on insurance and risk it...if the crap hits the fan it's nice to know the insurance will sort it out and you won't have to fork out thousands for the car you may have hit....
As for gear obviously you will need...
Helmet
Gloves
Boots
Jacket
Draggin Jeans (kevlar lined jeans)
and If you are going to ride hard full leathers and a back protector
I can't stress the importance of the proper gear enough...I have seen what happens when crap happens and you don't have the right gear on and trust me you don't want to go through it...
Anyway check out netrider for a bit more info and advice!