Here is a list of relationship/matchmaking sites that are located in Turkey or focus on Turkish audiences… Suggestions are always welcome…
1) Sites like OkCupid are increasingly used in Turkey…
2) I have not included any sites that focus on Gay matchmaking. In fact, I could not find… Gay focused sites I could find offer more than just matchmaking…
3) There are “chatroom” style sites… Probably they are also used for finding “friends” but chat based sites deserve another list:)

istanbul.net

yonja.com

siberalem.com

80630.com

gayet.net

sevgi.net

Relatively minor ones:

arkadassitesi.com

sevgiland.com

kolayarkadas.com

arkadas.com

arkadaslik.com

ozel.org

askmesk.com

sevgilimol.com

saklanbac.com

bekar.com

sevgitreni.com

sevgibul.com

randevum.com

islamievlilik.com

kalpler.net

kalbim.net

evlilikoyunu.com

arkadasbul.net

loginlove.com