The Anglicare adoption services at Telopea is a good place to start - you are quite young. (Adoption Services) 02 9630 7877
Though age is no barrier these days but when there are so few babies relinquished and birth parents help choose - they prefer younger parents and they have very right to participate wholy in decision making these days.
I think Catholic has Centcare and DOCs another
It isn't as costly as you think - compared to intercountry adoptions and you would qualify for baby bonus too if baby was under a certain age.
The main costs are for the counselling /interviewing involved and court /solicitor fees.
I don't want to offend you but have you tried IVF - your post doesn't say why ?
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