Your camera has a stereo mini plug. Buy a stereo splitter and you can plug a mic into each of the two pigtails on the splitter. Want to be more pro and use xlrs? Buy a beachtek xlr to mini box that will allow you to plug in two pro mics into the box and record them on the camera.
Get yourself a mixer. Behringer makes a good mixer for 4 mics that costs around $100. Great investment, especially if you plan on recording live events in which you can also receive a feed from the house sound board.