InterNations — Your Expat Community in Turkey provides essential information with an option for paid registration with the expat community. Membership allows you access to even more shared opportunities about living in Turkey.
Justlanded: Turkey provides resources and background for moving and living in the country.
Numbeo: Cost of Living in Turkey is a fine crowdsourced site that provides much aggregate and itemized information about the cost of living in the country, the main cities, and bigger towns which should help prepare you for the transition.
Turkey Travel Planner is a very rich site hosted by Tom Brosnahan, a foremost expert and author of books on travel and living in Turkey.
Lonely Planet: Turkey Travel makes it easy for travelers to deal with the daily challenges independent travelers face: how to get around, where to stay, where to eat, and much more.
Rough Guides: Travel Guide Turkey describes various attractions and destinations, while
also providing practical travel tips about transportation, safety, and other travel essentials.