The shopping scene in Tours is made of traditional morning markets and other, more focused consumer centers.  In the first category are different markets operating on different streets on separate days of the week.  The following list was nabbed from the tourist office website :

Tuesday : St Paul, Paul Bert, Bd Heurteloup
Wednesday : Halles, Beaujardin, Coty, Fontaines
Thursday : Strasbourg, Velpeau, Beffroi
Friday : St Paul, Blanqui, Rives du Cher
Saturday : Halles, Beaujardin, Coty, Coppee, Fontaines
Sunday : Maine, Velpeau, Rabelais
    
The flea market of the Place de la Victorie is definitely worth checking out, open on Wednesdays and Saturdays, and the Craft market in the Places des Halles, available for perusals on Saturdays, also makes for fun souvenir shopping.  For a fuller list of specialty markets, check here .

Tours is also a wonderful place to get gluttonous.  Try their macaroons, or purchase one of the wide varieties of white wines for which the region is also known.

There is a large shopping centre called "Centre Commercial les Atlantes" which is to the south of the city in the suburb if St.Pierre des Corpes, you can get there by bus No.8 destination Atlantes. The bus runs through the centre of Tours. In the shopping centre there is a large restaurant named "Flunch" which is one of a chain of French restaurants which you can find in most French cities.It has a large choice of self service food.