You can buy the best camera available and still take bad photographs.  The truth is, the camera wont’ make you any better at photography then a $2 point and shoot.  If you want to shoot like one of the many great professional wedding photographers, you’ll need some understanding of light, composition and technical options.  If you’re serious about becoming a good photographer, consider photography classes, online education and of course, take lots of photos every day.  There are many outlets to have your portfolio critiqued too so get some feedback.