Old San Juan, San Juan
Old San Juan is a place with lovely architecture, lots of history, and quite a few shops selling souvenirs. A lot of these are along Calle del Cristo or Fortaleza Street. I would say that in general, if you go further away from the cruise port, the souvenirs become a bit less kitschy, and you start seeing more art, artisan crafts, etc.
What to buy: Typical Puerto Rican souvenirs include vejigante masks, hammocks, Panama hats, larimar jewelry, Caribbean foods and candies, and rum. You can also get quite a few things with coqui frogs, the symbol of Puerto Rico on them.
Two places that we really liked were Spicy Caribbee and Ovalop. Spicy Caribbee has samples of all of their projects--different sauces, jams, and other products--and everything we tried was really good. You can also order things online from them, and I'm considering doing so because we really liked their products. :) Ovalop was a nice beading store. I got two strands of freshwater pearls for $6 that I made into a bracelet, along with some charms and amazonite beads. It's a nice option if you can't really afford some of the nicer jewelry in San Juan--you can make your own!
What to pay: We bought a nice hammock for about $50, my vejigante mask was $10 (thought it was smaller and in a different style than most), and prices seemed overall pretty reasonable to me. Rum was cheapest at the airport or at the Bacardi Factory (if you want Bacardi) though, so I probably wouldn't buy it in Old San Juan. Our favorite Puerto Rican rum was Don Q gold, which I believe was $14/liter at the airport.
I have been fortunate enough to have traveled to Puerto Rico my whole life and visiting Old San Juan is always a must do when I visit this beautiful island. There is so much to see and do while in Old San Juan. If you love to shop, then this is the place, not only can you find beautiful souvenirs but you can also find artwork and the latest fashions too. There are tons of wonderful restaurants serving native Puerto Rican food as well as American and other ethnicities as well. Finally, if you are a history buff then Old San Juan is the place to be. You can do your own walking tour or you can sign up for a local to take you around, but one of the best things to do is the Segway Tour, so much fun.
We visited San Juan just before Halloween. The cruise director advised us that masks were one of the things to buy there. We didn't buy any, but I did take some photos of the shops as we passed. One of the shops was a mask shop.
One of the more intriguing shops in Old San Juan was this MasK Shop. I have never seen anything like it. They were colourful, artistic, unique and some were downright scary. They were quite expensive but hey -- they're hand crafted. They would make a wonderful attraction on your wall.