Heading over to Turkey at the weekend with my new i Phone in tow. I'm new to this game so looking for some good advice. I'm on the basic £30 a month contract (300 free mins, unlimited texts etc..). Whilst I accept that I'll have to pay through the nose for any calls or texts I make, whats the score with internet and apps access? Will I get free wi fi access over there or should I forget about taking the phone at all?

Wouldn't bother taking it - you'll be charged a stupid amount for accessing the internet and most apps require you to do so (such as FB) - unless you really need to, I'd leave it at home.

well, you could take the phone, just go into settings and then network and turn DATA Roaming OFF then you wont get any surprise's, Although i do believe that your network should send you a text once you get to the 25mb mark then again at the 50 and then stop data all together, but i would check this with your network

As for WiFi, that will depend on the hotel your staying at.

When i went to Marmaris in Turkey last year, they charged wifi by the hour so it wasn't all bad. all i had to do was pay for an hour at reception and then enter a 4 digit pin and then i was in for an hour.

In the resorts most bars and restaurants tend to have free wifi so use that, but DO switch off Data Roaming.
If however you decide to use data on the Turkish networks, I know that with Vodafone, Turkey isn't included in the Europe zone, so data will be charged on the rest of the world rate - very expensive.
What I did was mostly use wifi, and on the odd occasion where there wasn't any wifi, I'd switch Data Roaming on to check emails then immediately switch it back off again.