I’m not familiar with any specific destinations in those areas but I would just google “hobby stores near me” or “card shops near me” or something along those lines. I believe Wizards of the Coast has a store finder that you can punch in a zip code and find official dealers. It’s mostly for MtG but there’s a good chance that a store that carries Magic will carry Pokemon products as well.
In Chicago there are at least 2 stores that sell singles and vintage: Galaxy Comic Zone and Near Mint Games. GCZ is a smaller shop and they sell some raw cards that they’ll show you stored in a binder - selection is not very big but they’ll probably have some vintage - but NMG has a much bigger selection of slabbed (mostly non raw) cards which includes vintage. They also have some vintage sealed packs and product as well.
So your best bet for raw vintage is GCZ but the selection is not huge.
Just a heads up: card shops in America are completely hit-or-miss.
Sometimes, you’ll walk into a card shop and find some gems mixed in for cheap prices among a bunch of otherwise ordinary cards. Other times, you’ll see played condition Jungle Kangaskhans going for $25.
There is a lot of trial-and-error involved, but if you manage to stumble into the right place, the experience can be very rewarding and satisfying.
Makaka Toys in NYC sold me a few of my cards for my 1996 set. I have not been there personally, but their website makes it sound like a brick and mortar place.
I can recommend a comc.com mailbox in US as an european buyer most of the stuff from usa i buy to be delivered in the mailbox and when i have enough stuff stored there i send them all at once to my country and pay shipping for only that one parcel. They do charge 2$ per order + 1$ per card but still loads of cheaper than paying those huge shipping costs overseas for everything