Hi There
Wal*Mart will sell everything you could imagine....and more!!!
For stuff like drinks and other food stuffs like snacks, Wal*Mart is cheaper. It also sells souvenirs like T-shirts that have Mickey on them but say Florida rather than WDW. These are cheaper than in the Parks. A kids official WDW T shirt will cost you around $18 in the parks, and I don't think the quality of the shirt is that special (but I still buy them......

)
Ponchos, squeeze breezes (fans with water sprays), film for cameras, luggage etc are much cheaper at Wal*Mart.
There is also Target - like the Big W here, sells everything!
I think really it all depends on whether or not you want to buy official WDW merchandise. Some of it I find irresistable - like the snowglobes!!!
There are bargains too though - in Belz there are some Official WDW and USF stores which sell everything at half price - I think it is mostly older stock, but still official. And you do get some real bargains, like half price snow globes!!!!
Hope this helps
Cath
