Eddis and Attolia from The Queen's Thief Series by Megan Whalen Turner
I'm not saying I want to hang out in the court of the King and Queen of Attolia because that would be scary. But I would love to see the mountains and the dystopia. Also I like olives and wine quite a lot so YUM! And I wouldn't mind seeing the greatest monarch couple ever from a distance. A very very far distance.
All the Restaurants, Patisseries, and Chocolatiers in Laura Florand's Amour et Chocolate Series
If you haven't read these books, you can not quite comprehend the level of want in this. Florand's description of desserts is absolutely sinful and will have you weeping for the lack of artisan pastry and chocolate in regular town America. A trip to France to visit all these wonderful places would be the best trip ever. (The shop I want to visit the most? It's a tie between La Maison de Sorcieres in The Chocolate Kiss and Dom's shop in The Chocolate Touch.)
Shrewsbury College at Oxford University form Gaudy Night by Dorothy Sayers
Sayers made up Shrewsbury, but it has much grounding in reality. A lot of crazy things go down there in Gaudy Night, but I love how it is a place where smart women do, think, and talk about smart things with each other (mostly getting along).
Dare Island from Virgina Kantra's Dare Island Series
Dare Island is a made up island in North Carolina's Pamlico Sound. I LOVE the Outer Banks and Kantra does a wonderful job of describing life there. And I want to live there now. Or at least be one of the tourists mentioned (though not as obnoxious as many mentioned are).
Chrestomanci Castle from Chrestomanci Chronicles by Diana Wynne Jones
I love everything about all the inhabitants of Chrestomanci Castle. The best time to visit would be sometime after the events of The Pinhoe Egg for getting to know the optimal number of awesome people. It would, or course, need to be during a time when Christopher was actually there.
Gardam Street from The Penderwicks on Gardam Street by Jeanne Birdsall
This neighborhood is the neighborhood I always wanted to live in growing up. It's actually quite similar to the ones I did grow up in on the military bases I lived on, but the families in those changed too often. I like the stability and community of Gardam Street.
Discworld from Terry Pratchett
I admit, I have barely begin to scratch the surface of this world. I just really want to hang out with Tiffany Aching and the Nac Mac Feegle.
Wellmet from The Magic Thief Series by Sarah Prineas
True, things are often exploding there, but I want to hang out with the leaders of this place because they are awesome. Also, one would never get bored while there.
Urwald from Jinx trilogy by Sage Blackwood
Another dangerous place to be, particularly at the point we currently are in this trilogy. But I'm certain Jinx is going to do something about that and then it will be truly awesome and not just scary awesome.
And of course, no list of places to visit in books would be complete without: