Where ever it is, there is an anime waiting there (presumably) because it is tasked with making sure you follow the instructions on the datachips. Anime in this context is talking about a metahuman form free spirit, not a cartoon. That means a) there needs to be sufficient mana to sustain the free spirit (i.e. not an asteroid) and b) the area should be hospitable to man (i.e the spirit would want to associate with man and thus be in an area with people around). Next figure out D's territory. D has multiple precautions in place to make sure that the mission on the datachips is done. That means he needed to have oversight of the whole thing. So it is a strong likelihood that the location is within his territory. Places in his territory are Lake Louise in Algonkian-Manitou then moved to Prince Edward Island in UCAS (North east). He's also got an island near Seattle. And here's a little bit of trivia often overlooked. He awakened at Cherry Creek Lake in Denver... 21 miles east of Red Rocks Amphitheater. He's got a lair in the Caucasus mountains (but I think that's just a nod to Earthdawn). He's also got access to anyplace Gavilan Ventures has, which is to say any place Ares is. While the Ares route gets him more locations, those locations are like 70% out of D's control, so not likely for this application.
My conclusion is that Where a Rock meets the Sky is someplace in North America, likely in the UCAS controlled areas.
Side note discovery while researching this. If you pull out a map of the indian territories and take a look up in the north east section of the Salish Shidhe Council where it meets up with the AMC. There's a sort of scooped out arc there that doesn't seem to follow any terrain or man made rationale. As it turns out, that's a 100 mile radius from Lake Louise. NAN picked out their borders well after Dunkelzahn picked his lair at Lake Louise. Notice the weird notch out of Sioux territory too. That's a 200 mile radius (roughly). It looks like, when NAN broke into various independent nations, somebody didn't want to deal with dragons.