To the south of the Cours Mirabeau is an interesting area to explore. If you need some reading material you can also find an English bookstore called Book in Bar Bookstore at #4, rue Joseph Cabassol in this section of town.
Aix has some of the best markets in Provence. Wednesday and Saturday there are many stalls lined up on the Cours Mirabeau mostly selling clothing but also table clothes and a free hand made items. I especially love the vegetable market held daily on Place Richelme which is right before you reach the Hotel de Ville.
You can easily rent bikes in Aix. Instead of being called Velibs as in Paris they are called VHello. Get it? Really though, Aix is so easy to walk around that unless you are going a long distance, you probably won’t need one.