Agra is well known for leather goods, jewellery and marble items inlaid like the pietra dura work on the Taj. The Sadar area and around the Taj itself are the main tourist shop areas although the prices here are likely to be more expensive. Around Pratapur there are many jewellery shops but if you are heading to Jaipur you 11 find precious stones are cheaper there. Subhas emporium in Sadar is a good place for marble. Beware of rickshaw-wallah taking you to shops they'll inevitably be raking off a commission at your expense.