Like HotI, I would just shop around for regular bags. I found a massive shoulder bag at Sportsgirl for $70 when DD was little & I used that. It fit everything in it for 2 kids for a whole day including cloth nappies/wipes/wet bag etc, two changes of clothes & lunches & drinks plus my stuff. It was fantastic. It had extra pockets on the outside so you could little things in there without them getting lost.