the cost of just a sim card was 15tl so may have gone up a little bit, as for the rest surely that is the phone that you put a sim in. you can use an english phone for a limited time before it is blocked normally about 2 to 4 weeks, also most cafes and hotels have free internet access, just cost you drink.
You can get a sim from the appropriate phone shop, dont think there is one in calis but there are lots in Fethiye, many of which have good english.
I am not very good at this sort of thing but hope this helps a bit. have a lovely holiday xx