I hurt my foot last year, nothing too bad and recovered now, it hurt in the arch and a little in the heel. It may be plantar fasciitis, it may not, not really sure, but it's probably similar. I went to a podiarist, they said I had very high arches and recommended I get custom made insoles from them. The type that lasted a year or two cost (from memory) $200, the type that lasted ten years cost more like $600 and you had to replace bits of it occasionally as they wore out. I suggested to them it seemed expensive for one incident, they agreed, and said to get some stock insoles.
I tried about eight different products, all from the US, because NZ has a really poor range, mostly from The Insole Store (great service, reasonable shipping). I came away with two recommendations, but one clear preference.
Sole Custom Footbeds are awesome. You put them in the oven for a short time (3 mins @ 100 degrees from memory), then put them into your shoes hot, the mold to your feet to provide really good support. Instead of my weight all being on the front, rear, and very little on the middle of my foot it distributes weight onto the arch and middle of my foot better. My feet always felt fine before, but they feel much better supported now. Without them walking feels a bit odd, even slippers - like my foot is working harder than it needs to. The casual model fits most shoes including tramping and business, and I'm about to try the response model which just has a different covering. The ultra model only just fit into any of my shoes, even the biggest ones, so I'd say avoid that one. US$40 each or so. I'm going to order a set for each pair of shoes I own later today.
Powerstep Pinnacle has very little arch support, but is nice and soft, very comfortable, with some support.
I have no association with the store or the brand, just sharing as it may help others.