
Re: how do i go about getting a work permit to teach english in istanbul?
It's usual to get a job (or at least the offer of one) before applying for the work permit. A reputable employer will then process the paperwork for you and in most cases cover the costs.
I worked in Izmir for 15 years and that was the case for me and other teachers I know.
You can compare others' experiences and join the discussions on these two websites:
http://eltworld.net/forums/viewforum.php?f=20
http://forums.eslcafe.com/job/viewforum.php?f=22
It has sometimes been suggested that you need to apply from your home country but I've never found that to be the case. They will need original certificates for both your degree and TEFL cert., the process can take a while and is fairly tedious but works.
Good Luck!