We stopped in the Tourist Information Office to pick up a free map of the town. While there we had a chance to look at all the other information they had on the city and region. The TI also maintains a nice little bookshop and gift shop. Because of the history between Xanten and the Nibelung saga of Germany, the TI had a number of gifts and books related to this legend. In addition, the TI has the Siegfried Museum located on site (Siegfried, the main character of the saga, was supposedly born in Xanten).
The personnel at the TI were extremely friendly and helpful as we asked questions and made a purchase.
The TI is located near the market square at Kurfürstenstraße 9. It is open Mondays through Saturdays from 1000-1700 and Sundays/Holidays from 1100-1600 (closed Dec. 24, 25, 31 and Carnival Monday/Rosenmontag).
I found some small flea market in one of the corners. some items there seems to be very old and untouched for generations, I was really wondering why they are still there, why someone should ever want to buy them. But the violin I wanted they asked too much to worth it.