The word Nesso is also the Italian name for Nessus. Nessus is the centaur who was the ferryman on the river Euenos.
The C30 Bus line (the blue Como-Nesso-Bellagio line) regularly serves Nesso. It comes through about once an hour in each direction and has three stops in the town. The bus schedule can be found on the bus website  in pdf form.
The ferry and boat service on Lake Como does stop at Nesso. However, because the town is so small, only the slower ferries with many other stops provide service to Nesso. The boat schedule can be found on the Navigazione website.
Like all the villages around Lake Como parking is at a premium. Day visitors can park free down the side of the church at the northern end of the village (about 20 spaces) or below the Tre Rose (see below) on the lake side of the main road.
It is quite common for stores and the like to close after lunch and then re-open around 3 or 4. Many stores are also closed on Wednesday and Saturday afternoon as well as all of Sunday.
There are two grocery stores in Nesso and they both follow this practice. One of the stores is on the street level (at the first bus stop in town - coming from Como) near the waterfall/roman bridge. The other store is down the steps to the north (towards Bellagio) near the church.
Like many of the roads around the lake, the roads in Nesso are very narrow and frequented by full sized buses and apparently suicidal motorcyclists. Try not to walk on the road whenever possible. The beautiful cobbled walking paths either below or above the road provide an excellent alternative.
The water by Nesso certainly looks cleaner than the water near Como. However, one should exercise some caution when swimming in it as recent water quality reports have shown the waters of Lake Como to have 68 times the accepted level of colony-forming bacteria. It is thought that this is from incomplete waste treatment.
There is a boat enclosure at the base of the cobblestone street known as Borgo Vecchio (Starts at the base of the church car park) which has a stone wall that is commonly used for diving/jumping from, sun baking and fishing. Swimmers can readily rescale the wall with built in ladders.