Hi,
Flash photography is challenging. Diving into flash photography can be rewarding, however I would strongly suggest you master the camera controls and relationships between settings (things like aperture, shutter, iso etc...) before throwing a flash into the mix. If you dont have the time and just want to jump right in and take pictures then if you put the camera in green mode and then set the flash to p-TTL, everything will be automatic and hopefully the camera will get the exposure right more often than not. If you are interested in spending (considerable amount of) time in learning the settings and using manual flash the rewards can be amazing. One places I think is a good start is David Hobby's Strobist blog:
Strobist: Lighting 101
It is very informative and a great intro to flash photography!