Hi Lewis,
Perhaps as a starting point you could look at the information on
www.immi.gov.au, the Department of Immigration's website and search for partner visas.
Basically, you may sponsor your partner for a spouse visa if you are married to him, a de facto (spouse) visa if you can demonstrate 12 months cohabitation, or a prospective marriage (fiance) if you plan to marry in Australia.
The key to all partner visas is the evidence of relationship. You need to submit as much documentation as you can to show that your relationship is genuine and ongoing.
In regard to your plans for marriage, you say that you wish to marry in Turkey and then marry in Australia. Is that due to religious considerations? Where you marry and how you marry is relevant to the type of visa you can apply for.
Hope this helps,
Kind regards,
Vicki