Upvote:1
If you want to go out of the airport for shopping purposes you would need to apply for an e-visa.
Citizens of India are eligible for an e-visa and it will be processed in 1-2 days (i think within 24 hours). It is a completely online process i.e. application and payment. It will cost USD 40-50.
You can follow this link
However, you need to assess if 5 hours would be enough to first pass through immigration & exit the airport, travel to someplace for shopping, browse and buy and return to the airport and pass through immigration for the flight in time.
There are a number of shopping options at the airport too. You can have a preliminary look at http://www.ataturkairport.com/en-EN/airportguide/Pages/Giftshops.aspx