Wow, that's terrible!
I'm 25 & with Shannons (have been for 3 years, prior to that I was with AAMI then Just Cars.) They definitely insure under 25's, you just have to be the right sort of person.
My R34 GT-T is $1,200 per year and insured for $20,000.
My highly modified Pulsar is $1,100 per year on limited use cover and insured for $15,000. I also have full salvage rights to the car at no cost in the event it's written off. I pay a bit extra because of this.
My insurance would be much cheaper save for having my cars insured in a very high risk suburb. Price includes my CAMS license discount.