Amboise has a pleasant clutch of cafés along Rue Nationale and around the main square below the chateau. The terrace of the Café des Arts on Rue Victor Hugo is a standard gathering spot for an afternoon glass of Vouvray or Touraine Amboise. Le Shaker on the main square has a more cocktail-bar feel in the evenings.
For wine, the place to go is La Cave du Roy on Rue de la Tour, a wine bar with a well-chosen selection of Loire wines by the glass — Chinon, Bourgueil, Vouvray, Montlouis — with the owners happy to explain the differences. It's one of the better reasons to linger in Amboise after the day-trippers have gone.