I love the skinny corn chips. I usually buy them online from
coolfruits.com. They usually run about $12/case and that includes shipping, so that's about $0.50 per bag.
The only other place I've seen them locally is Wild Oats or Beans, Grains, and Things. I'm not sure if you have one of those stores locally. A 4 oz bag there runs about $2.00 which is a little pricey. They don't carry the 3/4 oz bags as far as I know.
Hope this helps.