i would research "where" i want to go to college -- i mean locations, states, cities -- then research schools -- at all levels -- in those areas that have quality academics and have your desired "majors." make a big big list. then cross-reference that list by track times in your events for those teams -- that you can find off TFRRS. the teams where you like the area, have the grades and scores, and fit in their level of runner, that's your wheelhouse. start there, do the questionaires and email the coaches with a set of information, GPA, SAT, events run, PRs, key finishes in big meets. include XC if you want to do that in college.
if you start wheelhouse then move up, then you know you will have all else fails the interest of X Y Z schools who need someone exactly like you, no improvements required, no magic enters the formula. having stirred that up, only then start working on reach schools, higher academics than you have, faster runners than you are.
the big mistake kids on here repeatedly make is they start with dreamy reach schools and forget to have safety schools and places where they are admitted who want them to run. if you have done your job at step 1 -- picking areas you like, with academics you want, where you can run -- then your "worst case scenario" is a town and school that make you happy anyway. if you let dreaminess drive, you either end up hating the schools you let recruit you, because they are picked for ego reasons and not actual fit, or you end up the sad sack on here pouting because the one school he applied to, with the idea of walking on, has either told him no, you can't make the team, or the track coach has no clue he exists. so work your way from wheelhouse outwards. then the core schools and track teams definitely know you exist. it's a much more fun process to be wanted and mutually happy, than to be desperate.
re "d3 stereotype," if you do the process i laid out, you will find that there are in fact a mix of D1 and D3 in the locations you want to be. that alone deals with your "all D3 are in cowtowns" stereotype. yes, many D3 are in rural cowtowns, but there are also plenty of D3s in cities along the pacific coast, LA (a whole conference in and around the city), santa cruz, portland, seattle, as well as schools in eastern cities, NY, chicago, etc. and good academic ones. UAA has a bunch of city schools. NESCAC is a mix of rural and city schools but they are all at least good if not great academically.
re D1 vs. D3, you would already make some D1s, honestly, though currently not the good ones. you would have limited options. you would be very competitive D3. personally i would ignore the labels, and do the analysis i laid out. find schools that will make you happy and would want you to run there. my one caveat on all this, is understand from your standpoint, D1 is small fish big pond. imagine you are chasing whatever girls win your races. now make 95% of the field a xerox of those girls or better. that's D1. D3 you give up that but it's mostly runners like you. you will have a chance to score points in meets, to have success. having been at a D3 that often ran against D1, it was cool but also the vague desperation of fighting to move up the standings from near bottom. and people have dreams of escaping that, and some walkons do, but like D1 aren't scrubs or lazy folks, generally. when you're dreaming about how it's going to go, remember your team and the other teams are full of kids with the same dream and plenty of work ethic. it's like an ego thing where if i just go there and they let me walk on i will dominate. realistically it's maybe you'll be the one kid who goes from nowhere to scoring a couple points at conference as an upperclass.