Rauch:
Have someone stand next to you while you shoot and have them listen for any noises that your bow may be making. You can probably reduce a lot of the noise by adding limb savers to the limbs. Also, tighten all of the screws and bolts on all of the accessories. Moleskin on the sight window will reduce the noise of a arrow falling off the rest at an inopportune time. Check your arrows in your quiver to make sure that they are secure and not fitting loosely. If you have an accessory on your bow that you can't quiet down sufficiently, buy a new one. It's not worth losing a buck over. This should help get you started.