#1
What tips can you give me about finding a good guitar teacher? In what way should i conduct my "job interview" and what questions should i ask him?
#2
I dunno, when you find out, I'll be curious to know. Have been dissatisfied with the two I've had to date.
Fender American Deluxe Stratocaster
Epiphone Sheraton II, Seymour Duncan Jazz and '59.
ESP Horizon NT II
Epiphone Les Paul Custom
Mesa 5:50 Express
Egnator Rebel 30
Hughes and Kettner Tubemeister 18
#3
Well there's not much you can do over the phone.
A good teacher should be concerned with what you want to learn. So if they don't ask you what your musical preferences and intentions are, then that's probably a bad sign.

But, in the end, the only way to find out if a teacher is going to be helpful to you is to turn up and take a lesson or two. If the first teacher you go to doesn't suit you, don't give up. It would be worth trying a different teacher.
Learning a new cover song? Feel like recording it? And have people listen to it? See the CATPM thread in the Pit. Here's the user group
#4
In my opinion you should really focus where you want/need to improve upon. For example if you have a lack of coherence in your play or you keep playing the same kind of riffs and licks and you are stuck there, look for a teacher who has a lot of knowledge about the music theory. They can teach you how your music makes sense and you could play further from there. Make a list of your your weaknesses and strengths and find a way to improve both.

What also helps (I know someone who did this): Go to your local music shop and ask the employees if the know some good teachers. Really often they are in touch with good musicians so they should be able to give you some names and numbers and you can start contacting them.

At the end it is the ombination of skill, way of teaching you like and opportunity to improve where you are looking for.