You can visit Crystal's site here to see her updated post on things you can buy for free or cheap at Walmart!
I personally use to be a "Walmart" shopper! In the 2 years that I have been seriously using coupons I have only gone into Walmart to shop by these lists that various blogs post (equivalent to about once every month but mostly once every 2 months)!
Sometimes the prices vary and sometimes a specific item might not be carried in your particular store but it is still worth the trip!
I have gotten many "free" things from our local Walmart! If you have never tried using coupons at your local Walmart you may want to print out their corporate coupon policy here and take it with you!