I don't know much about Audio,....so I won't say much except for that fact that I like JL...also Pioneer makes great head units and awesome replacement speakers.
Fog Lights: Blazertech are good, but the latest rage is Angel Eyes from Hella a good website to find random car goodies is www.pfyc.com
Have fun and check out http://www.bonnevilleclub.com/techinfo/?article=52
Also, in case you were going to ask, its really really tough to supercharge your Bonneville SE
Good reading material here
Diamond White Classic Aurora - Back on the Road
Galaxy Silver Grand Prix GTP CompG - Soon to be mothballed