Ok here's where some of the best weapons in the game are:

Sub-machine guns-In the fountain in al fresca plaza, on the platforms near the stairs in paradise plaza, one on top of the italian chef in the food court, and one in the maintennace tunnel in the garage.

Chainsaw: on in the hardware stores one in alfresca plaza and one in north plaza.

Small-chainsaw: defeat adam the clown and they will respawn in the same place, also get the books in paradise plaza bookstores and in wondorland plaza bookstore.

Battle axe: in the antique shop in entrance plaza.

Shotgun: get at beginning of game from survivor near stairs to right or after you defeat cletus in the huntin shack grab as many as you need.

That's all! enjoy your killing!