sounds like you have someting going to ground. Need to do a draw test. Disconnect the neg batt cable, take a test light and touch one end of the test light to the batt ground cable, then take the wire/clamp end and touch it to the neg post of the battery, effetively putting the test light inline with the batt neg cable. If the light lights up, you have a draw. Then, you can start pulling fuses and if the light goes out, the draw is in that circuit, provided there is only 1 draw.
BTW... did you have the battery tested ?