I am citizen of Turkey with a Tourist visa for Canada. My flight is from İstanbul through New York then Toronto.
Do I need a US visa for my transit journey?
By the way, we are not ESTA member.
Yes, you need a visa. The United States does not recognize the idea of visa-free transit, you will have to go through Immigration and then go out again.
The US has a C-1 Transit Visa that's supposed to be used for cases like yours, but this is apparently just as is difficult, time-consuming and expensive to get as a regular visa.
Is there any way you can change your flight not to go through the US? There are plenty of direct flights from Canada to Europe.