I use Italian sausage meat from our local deli usually, but on other occasions I have bought fresh Italian sauages & skinned them and used the meat.....think really chunky red spicy italian sauage meat........

(That recipe is very forgiving BTW.......you can fiddle about with it a fair bit........it also makes enough meatballs for 2 meals for us, and tastes better the next time round IYKWIM?)