Apple iPhone accessories are made to further maximize the use of the features provided by the famous iPhone unit. Some accessories are specifically made to provide protection and storage for this hi-tech, expensive gadget.
don't know too much about cases, but I would say Sena Milano cases. For earphones, I need to know you budget, I would say the Klipsch Image S4 (80USD), Etymotic hf5 (150USD) Monster Turbine (170USD) Shure SE310 (250USD) Klipsch Image X10(350USD) Sennheiser IE8 (500USD). but again, these are just some good earphones in different price ranges, first I have to know your budget, what type of music you prefer, and it also depends on you taste (some people like lot of bass and dont care about mids and highs, and some doesn't). So I would recommend to go to an apple store or somewhere where you can try out those earphones, and then buy it.