There are quite a number of bus lines that run regular transfers between Naples, Sorrento and the Almalfi Coast. It is approximately 50km from Naples to Sorrento and will take a little over an hour depending on traffic. There is also a train service that stops at Pompeii and various Ferry services that travel directly across the bay. For visitors coming from Rome there are also regular bus services that generally take 3 to 4 hours to travel to Sorrento.
Within Sorrento itself, there are a number of bus services for travel around the town or to Positano and the Amlfi Coast which are well worth the effort. It is suggested to base yourself in Sorrento for a few days and spend a day taking the bus over to Positano and back and similarly for the island of Capri. Depending on the position of your Hotel within Sorrento, you may find that you can easily walk to many of the places you need to go within the township. There are a myriad of quirky little souvenir, fashion and food shops, restaurants, and romantic or spectacular vantage points to explore. Your Hotel reception will usually help you find the right bus, taxi or walking route.
The ferry trip from Sorrento across to the island of Capri is extremely popular and for good reason. The ferry takes about 25 minutes and runs regularly although it can be quite crowded in peak times. On the island you will want to see Anacapri and you will need to take a taxi or use the bus service. The other unmissable attraction is the Blue Grotto which you can get to by water with a charter company or walk from Anacapri.