Umut -- at one time the U.S. Foreign Service (Department of State) had an Arabic language school in Tunisia -- it had been in Beirut but had to leave when troubles began there. I attended this school for one year in the mid-90s after having completed one year of Arabic in Washington. We were learning "modern standard Arabic", which is really something like what a Jordanian or Palestinian would speak, and our teachers knew that was our goal as we wanted to have an Arabic that was useful across the Arabic-speaking world. Perhaps you already know that there are several levels of Arabic -- Classical Arabic, TV-announcer Arabic (more formal than local dialects), and dialectical Arabic. My experience in Tunisia was that Tunisians would go to great length to speak to me in French (which I also speak), English (ditto, usually), German, Spanish -- but not Arabic. So if you're thinking that you'll hook up a local Tunisian and learn Arabic, you'll certainly learn something but it may well be local dialect unless you are certain to find someone who can teach the more broadly-applicable standard Arabic. Choose your teacher wisely, and you'll have a great time. Be sure to travel around the country; just be watchful of your safety. My time there was before the Arab Spring, so security was less of a concern.
