Limon: the "stalls" on the Pier are a great place for wonderful leather bags. Got my favourite carry-on duffle there 9 years ago for $40.00 and still use it every trip. Was in Limon last year and the same style bag is now up to a whopping $45.00! It is wonderful leather. Also some great buys on wooden salad bowls, tongs, wine racks, etc. You have to pick through the usual souvenier stuff but there are some great buys on the piers.
The Jungle River trip should not be missed. I would recommend a ship's excursion as some people I spoke with almost didn't make it back to the ship in time. I was also with some people independent from the ship, but our guide made sure we were back in plenty of time. Guess it's just a matter of luck.
In all, I found the people of Costa Rica a delight - very friendly, sweet and kind.
Just returned from Cozumel and Grand Cayman a few weeks ago. Depending on which pier you dock at, Cozumel has a new (to me anyway) shopping plaza at the end of the pier. It's very modern, many shops. The silver is great and the prices on coffee and coffee liquers quite good.
Grand Cayman had 7 ships in port the day I was there in late Oct. It was a madhouse! Wall to wall cruise pax in the downtown area. Took the first free cab I saw and went to Seven Mile Beach for the day. Didn't shop much - just a flag for my collection.
Ocho Rios has some pushy vendors but a firm "no thanks" seems to do the trick. I'd use cash or travelers checks there as I didn't feel safe leaving my credit card # for some reason. There are a few upscale jewelry stores, but mostly the wood crafts are lovely and nice mementos of your trip.
Dunn's River Falls should not be missed if you are physically in fairly good shape. Tough, slippery walking up the falls, but worth it when you reach the top!
Bon Voyage!