food is the biggie too i reckon. Avoid the Big Two supermarkets like the plague for your main shop. Seriously just go in for the cheap milk and bread. we do alot of ALDI and after alot of research for our family it was cheaper to get a fruit/vege box delivered. you dont choose the contents, but it does keep life interesting lol.

Meal planning is key. Can be a PITA to get organised but once you have the knack it is totally awesome, it streamlines shopping too.