As far as I know, Southern India is a hub for beautiful Silk Sarees. Range from low to high, traditional to fashionable and light to bright, all kind of silk sarees can be seen and purchased in ample amount day to day.
As far as I heard, on Quality, Design and Cost, Chennai gives you a best option for Saree Purchasing.I made visit to chennai for couple of times and roamed around the big shopping area of T.Nagar. It has many saree retail stores like Pothys, Chennai Silk, Sri Krishna, and many more. Making visit to all the store will take the whole day, but its worth enough.
The range starts from Rs. 2000 onwards and goes higher based on the quality of the sarees. The color combination and lustre of the saree can attract anyone.
I noticed varieties of modern print silk sarees on shelf and sale in different shops.
If you are visiting Madurai, TamilNadu : Nalli Silk, Pothys are good choices of shop for silk sarees.
In bangalore, I found different varieties of silk sarees like paper silk, raw silk at Nalli Silk Shop and for modern designer saress one can look for Rajalakshmi Textiles or Soch. Many other shops are there as well in chickpet area, but could not make a visit till now.