Haha, Bro Spitzer, welcome to the forum, and welcome to Sydney if you choose, you'll be in punting paradise !
Let me try to answer your questions one by one :
Yes, the prices stated on this forum are all real, $150 to $200 per hour in most Asian brothels with good service, then you have the higher end ones like 5* at Wooloomooloo where they charge up to $280 an hour, or non Asian ones like Christine McQueen's parlour and Stiletto at $350 to $400. Also you can get fresher and younger Asian girls ( many of them are not professional working ladies ) at outcall Agencies for $300 to $400 an hour.
For Koreans only establishments, Try Golden Flower, AngelTown, Styles, Eden etc. although you can also find some stunning Koreans at 5* City. For Japanese, Tokyo Model Agency is the best known one, but it's outcall style operation. Then you can try Ginza that features a lot of Japanese too.
If you have further questions or if you want to know more in details, this forum is the best place to ask ! Welcome again !