I think Aix would be a good base. There are tours from Aix but I don't know if there are as many to choose from in November as there were last month when we were in Aix for a week. We chose one to Cassis which was fine. We would have chosen more including to Avignon and Luberon but as we had a hirecar we went under our own steam including a visit to Dignes and the tour of L'Occitane factory in Manosque.

The Tourist Office in Aix is a mine of info and we booked our hotel through their website. See my review of Le Mozart Hotel on Aix-en-Provence TA Hotels Forum. I think you are aware you need to get the TGV from Paris to Aix and the TGV station is a Navette busride away from the city.

Ahh, the triple A! You will fall in love with these towns, just as I did!

Some extremely helpful websites:

Aix Tourism Office - Visitors' guide:

aixenprovencetourism.com/uk/aix-visiter.htm

Find attractions, museums, and city tours.

Guided Tours of the Aix region:

aixenprovencetourism.com/uk/aix-excursions.h…

For Arles, I suggest the Arles + Roman Heritage + Van Gogh Sights. If you do a CAP tour, say hi to Georges for me! All tours depart from the Tourism Office, located in the heart of town at Place Charles de Gaulle/La Rotunde AKA the giant, beautiful fountain.

City Tours of Avignon:

http://www.ot-avignon.fr/pages-en/home.htm

Another first class Tourism Office site. I recommend taking the train to Avignon independently. Both Aix and Avignon have TGV stations outside the city as well as shuttles connecting the town with the station.

Aix is pretty well-connected, you can get to a lot of places you might want to visit by ordinary public transport (cheaper and you choose how long to stay) as well, plus there are loads of places to eat there. to be honest though I don't like it as a town much, i think Avignon is a better base than Aix, and you can get to other places very easily from there.

I agree with ChicChantal - if you have limited time then Avignon is a better base for the towns you want to visit. You don't actually need organised tours, just a map and guidebook for each town, as there are regular trains to Arles from the town station, and to Aix TGV from the TGV station just outside town (with a regular shuttle bus service to the town centre). You could spend your arrival and departure days in Avignon and Aix, with the full day in Arles, as there is such a lot to see and it's good to be able to take your time there.