Check out Brian Keene's "The Rising" if you're looking for a good zombie tastic novel

That would be nice... but, as I said it before, semiauto smgs are illegal, so, nobody sells them (and you won´t find them in any gunshop). The only way to get one is (in case of zombie apocalypse) stealing it from the police,

Id end up looting most of my weapons anyway, a m16a2 looted off the body of a national guard soldier has more firepower than my savage mk2.

Looting is a great way to get your ass capped, either by the object's owner, that guy's buddies or other looters

A zombie soldier/cop with one slng/holstered, an abandoned police station/patrol car/mil vehicle, are good bets.

It'd be a pretty good way of stocking up on ammo/magazines/spare parts if all the zombie cops/soldiers were all carrying the same guns

Too many videogames my friend :D. If you want to loot, do it quickly, ´cause the police stations and ammo depots will be the first to suffer it. See the haitian disaster, the supermarkets were the first to be looted.

The point of talking about this now is being prepared!
So, you want to stock up on all the stuff you can get legally just in time!

That way, when the zombies turn out to be manifestations of dark magic or something, you can plink away with no effect as they shoot fireballs and summon skeletons or whatever. So much for theory!

I have no idea what zombies are going to do to me when they show up.

The whole reason you stock up on ammo is so that you won't have to worry about supplies because if you don't have enough you can just go take them from someone else

Ahh!
Use a crossbow. I believe one is recommended by the ZSG 'cause it's quiet and ammo is somewhat reusable.