Check on the waiting period for your private health insurance, I think you can claim for dental after 2 months (if he can hang on that long!)

Also shop around, sometimes you can get deals where if you sign up they will waive some waiting periods which will usually include dental.

As for a dentist, I see you are in Armadale. Just down the road in Malvern, on Station Street off Glenferrie Road, is Mint Dental and they are excellent. I saw Marianne Kagiaros when I was living there but she only works part time so can be a bit hard to get into...but I'm sure anyone else there would be just the same.

ETA: You don't have to have PHI to go to a dentist, but you'd have to cough up the full amount at the time of treatment.