Hmm... I think this thread is very interesting; guess I'll give it a try! ^^
Since I live on a bit of a hill and near a pretty deep wood, I can guess at there being a lot of Ground and Grass types; probably most dominantly being the Oddish line, Roselia line, and a number of others; not including Bellsprout line, however. Tropius would also take a miss. As for Ground type, and even Normal types, we'd likely have a lot of rodent-like Pokemon scurrying around; including Ratatta, Pikachu, Sandshrew, and others, as well. Pachirisu would be pretty common, because we have a lot of squirrels around, and there'd also be a lot of horse-like Pokemon, as well as Cow and Sheep-like. (Ponyta, Camerupt and Mareep, respectively)
There would definitely be Ledian and other such bugs, as well; probably including Spinarak, despite the spiders that live around here aren't venomous. Unfortunately, we also have a lot of bats, so Zubat and such would also be rather common.
But the plus side would be that we have foxes; Vulpix and other such fox-like Pokemon would be rather abundant, so that would make me rather happy. ^^ Household pets, which would likely consist of cat-like Pokemon, would be rather common, as well, since there are a large number of cats where I live, and most likely dogs, like Houndour and Growlithe would be rather common, too.
I'm going to be predictable and say that Eevee would be a common sight, as well. Because I'm a huge fan of Eevee and also situate Eevee as being a fox... or fox-like... XD
As for Water types, there would be no end to Magikarps, since there is quite a bit of shallow water, shich tends to be a common thing for Magikarp to thrive in, but there would also likely be other water creatures, like Surskit, and such. Butterfly and Moth-like Pokemon would also be rather common; especially around the warmer seasons... and unfortunately, Beedrill would probably be rather common... ._.
That's about all I can really think of, at the moment, though. I live inland, so there wouldn't be that many Water types around, however, there is a river, not too far from where I live; there would no doubt be a greater number of Water type Pokemon, in there; (Goldeen and such) not to mention ducks. (Psyduck, Golduck)
Hmm... that's about all I can think about, right now.