T.S.
I know exactly what you are going through. My daughter is the same way. She has long super skinny feet that are VERY hard to fit. When she was just starting to walk, I used those soft soled leather shoes. They now have them at Target for a reasonable price. Then when it was absolutely necessary, I went to Stride Rite for her shoes. Expensive, yes, but I believe children need a good fitting shoe. I found a Stride Rite outlet store where I could get two pairs of shoes for what one pair cost in the regular store.
I have also found that different brands of shoes fit very differently. Nike tennis shoes are narrower and fit my daughters feet. Where as Sketcher's are quite wide. J C Penney's has some shoes that are made narrower and fit her feet quite well. They are quite a bit cheaper than Stride Rite, especially when they have their buy one get one for 88 cents sale.
It is getting difficult to find her shoes now that she is 5 and quite opinionated about her footwear. It is quite a balancing act trying to find reasonably priced shoes that fit and that she likes. If they don't like them, they won't wear them! The poor kid loves shoes and only gets about two pair per season. One play pair and one dress pair.
Good luck finding shoes. I know how difficult it is.