Does anyone know if there are shuttle buses in the port La Goultette, to downtown Tunis?
If you are on a cruise ship, stopping in La Goulette, I hope you speak some Arabic! I'm told there are "taxis" but I personally wouldn't want to hire one. I've been to Tunis in better times than there are now; even then, I would have been ill at ease without a large group. I, too, will be stopping in Tunis from our Holland America Cruise ship in September. I want to go to Sidi bou Said - ONLY - and have not found a way to do that, either. Good luck!
I stopped in Tunis on a cruise ship before the revolution, there were 4 of us and we hired a taxi right at the port for an allday tour. It was fantastic but a little crowded with 4 of us. It cost about 100 Euros including a tip. We went to all the spots we needed to go to. I highly recomend going this route.
There are taxis at the port terminal; the fare into central Tunis should be around ten dollars as I recall. Make sure you can see the meter running. Knowledge of Arabic is certainly not needed, but basic French helps. You could say "la Porte de France" (the eastern entrance to the medina, the old city) to the driver. If you're coming on a cruise ship, I wonder if the cruise line arranges its own shuttle buses. I guess some lines do, some don't.
Hiring a car and driver for the day is a good idea. There's at least two full days' worth of cool stuff to see in Tunis (e.g. the medina, the ruins of ancient Carthage, Sidi Bou Said, the American military cemetery, the Bardo museum), so that would be a good way to fit in as much as you can. I'd suggest going on Cruise Critic and seeing if people have posted about arranging private cars, in advance or upon arrival.
We were in Tunis several years ago off of a cruise ship and did what others have recommended. There were no shuttles at that time. We will be there again in late Sept but now I am not so sure. The state department warnings are not good for Tunis. We may just spend the day on the ship. Am surprised that Holland America is stopping there if there was any problems.
I looked at the State Dept. warning for Tunisia; it's a reaction to the attack on the embassy in Tunis in September of last year, after that film lampooning the prophet Muhammad was publicized. On the other hand, the U.K. Foreign Office states, "most visits to Tunisia are trouble-free" and just warns against travel to a national park far to the southwest of Tunis. I'm pretty sure there have been no instances of American citizens singled out or attacked in the country (and no Americans were injured in the embassy attack). I would visit Tunis now, but of course it's a personal decision. As I recall, Holland America caters mostly to Europeans, so they're less concerned. In general European tourists far outnumber Americans in Tunis- Americans can "blend in" and not mention their nationality if they so choose.