Another tricky one. The land does seem to have its own influence, which is worth paying attention to, but I'm also not sure it's as simple as "some Gods can only be meaningfully worshipped in some geographic areas." For what it's worth, I live in coastal Texas (Houston), and I feel like my worship of the Germanic Gods works just fine, and I feel just about zero pull to any of the Mesoamerican Gods - but then, I'm culturally and genetically pretty much entirely Anglo/Northern European. For whatever reason, it seems the Germanic Gods have pretty actively sought out worshippers in America, seemingly mostly among its European-derived folks, but obviously not exclusively. I've heard from a handful of European heathens that they sometimes feel like all the action is over here. My own hope/feeling is that Germanic Gods can/will have a role to play here, but as it develops, it will likely take on a distinctly American flavor different from what it looked like in Northern Europe. The culture and history of the American west has certain resonances with the "frontier" experience of Scandinavia and Iceland, which might suggest penetration further west than you might expect from climate or other historical patterns.

My approach is just to do what seems right for me and to offer it as an example to others, and to see where that goes, but I'd love to hear what others think.

Cheers,
Jeff