There are already some great replies here but thought I'd chime in with a few other suggestions since I'm in a similar region. A few other fruit trees that grow well here include paw paws, Asian pears, and serviceberries. Not sure if you're exclusively looking for tree suggestions but elderberries, Nanking cherries, and currants (though these are not allowed in many areas due to being a vector for white pine blister rust, so be sure to check local regs and/or stick with the rust resistant varieties) are quite productive here too. We also have success with hazelberts (if you can beat the squirrels to 'em), butternuts, and black walnuts if you're interested in nuts. The folks I know who grow figs around here (Chicago Hardy or Brown Turkish) generally either protect them in winter (wrapping them and/or having them in high tunnels) or have them in pots and bring them inside, though I'm thinking of trying some out in a sheltered, south facing spot to see if they can overwinter on their own. This year I grew maypop (Passiflora incarnata) from seed and the plant did set fruit but the squirrels ate them all long before they matured so not clear whether they would have matured before frost. I'm hopeful they will overwinter here but not certain - that species is sometimes listed as hardy to zone 6 and sometimes to zone 5 - but if they do and I can protect them from the squirrels next year then perhaps I could get mature fruit. IMO, they are worth growing even without fruit for their incredible, tropical-looking and -smelling flowers and the medicinal foliage. There are some varieties of prickly pear hardy here too but they can be hard to find. I know Edible Acres was selling some several years ago but I don't believe they have in recent years, at least not online.
For sourcing, I second the recommendations for St Lawrence Nurseries and Fedco (they have separate catalogs for seeds, potatoes/onions/exotics, and trees/other perennial planting stock). The maypop seed came from Experimental Farm Network, which has some other great stuff too but only some of it will be hardy here since their seed growers I believe are spread throughout the Northeast and Midatlantic regions. They have a couple of varieties of prickly pear seeds which are from further south so might or might not work in zone 5. For regionally adapted seeds, I'm a fan of Fruition Seeds and Hudson Valley Seed Company, though I don't believe either carry any perennial fruit seeds/planting stock. I did get saffron crocus tubers from Fruition though!
This is my first post, so I hope something in it was useful!