ive gotten some great shots wtih my G1.
put it on manual mode, turn macro mode on, zoom all the way in, put it about 12" away from the object you're shooting, press the shutter button half way down, let it focus, then press it fully to snap the shot. if the object is moving, you will need to press it half way down, then follow the object until it is some-what still, then press it down to snap the pic.
try that out. it's pretty basic way to start off. usually, i'd turn the flash off too.