I agree with J-Bar, most beginning and intermediate shooters will gain more speed with good transitions than they will trying to shoot faster. Read Doc Shapiro's book. Evil Roy tapes helped me along with lots of other good videos. Be careful trying to gain speed dry firing, I'm not always honest when I dry fire and have misses when I go to live fire. You can get so fixated on making a faster par time and think "I was close enough".
Move on the start of the beep not the end of the beep, move fast when reaching for guns, move fast from one location to the next, don't stroll along. If possible always try to practice with someone better than you, it will make you work harder.