First of all, for turkish hc punk history (1978-1999) I can suggest An Interrupted History of Punk and Underground Resources...
For mp3s, basic information etc. you can use the blog Clouds of Cancer
If you ask me, the best hc bands in Turkey, I would suggest to check these bands:
Radical Noise RIP
You can use Noizine!
Actually, it's not a good time for turkish hardcore because a lot of people are angry and bored working on it because of the lack of interest. Most of the zines, bands, distros are not doing anything at this time.
The last big concert in Turkey was Oi Polloi at Resist Fest and there was not enough tickets for costs (band's travel costs, sound systems etc) but I hope it will be better this year but I'm not sure. So, we are not in good mood at this time about hardcore :)