Of course we visited the famous bazaars—the Grand Bazaar and the Spice Bazaar. The Grand Bazaar is a grid of congested streets that amazingly house 4000 shops. After a while it seemed like all the shops sold the same cheap but overpriced stuff (since this has now become a major tourist attraction). We didn’t stay long. Maybe it was because we had already done so much walking around the city and we came late evening, but I did not have much enthusiasm to immerse myself into the shopping crowds. The Grand Bazaar is one of the biggest and oldest covered markets in the world [with 250,000 to 400,000 visitors every day], so I can't say it's totally unimpressive.
The Spice Bazaar, on the other hand was a total wonder. It is the second largest bazaar in Istanbul after the Grand Bazaar. Every shop had neat little piles of colorful spices and teas, each labeled. The shop owners invite you to stop and taste the spices while they give you some info about them. Each smelled and tasted so distinctive and oriental. I wanted to buy a little of everything and cook up an exotic storm back home. But alas, no room.
Turkish Delight [or Lokum] is very common, though not my favorite. It's made of gelatin, water, cornstarch, and sugar with added nuts or dried fruits.