It actually is Wonderland. There's just more to it than any version of the stories happened to mention. And as far as where this Wonderland is located... well, your guess is as good as mine. It seems to stand on its own, separate from any universes those of us here might be familiar with.

[Her smile is gentle. It's a lot to wrap your brain around.]

I know it's a lot to take in, and doesn't make any logical sense, but a lot of this place does that. I'll do what I can to help, though.