Here in Wisconsin it is legal to have one as a pet, but you might need a special permit.
The biggest issues are that you can't seem to get them vaccinated. And if the fox ever bit you are some one else it would have to be put down.
All "tame" foxes are usually hand raised and must be handled daily.
The fox I was offered had been left in a large wooden crate/box for two weeks due to the owner going away on vacation. He had reverted to a near wild state.

There has been an experiment going on in russia and a few other places. They took foxes from the fur trade and started breeding for docility. Long story short, they got foxes over progressive generations that barked, had floppy years and spots. In short they created a very dog like fox.
You do have to realize that a fox is still a wild animal, despite being hand reared or the like. They require a certain amount of space, excersize and feed. They are very very smart and may not acclimate to the presence of a lot of humans, or young children and prefer to be around only one or two people.
Also they tend to be nocturnal so when you are sleeping.. they want to be active.
Just an FYI..
I would talk to the folks at Wolf Park in Indiana, they have some foxes and I beleive half were from the pet trade. They have a website and are more than willing to answer questions.
They come and do a presentation on slides and on the park itself every year at a convention I go to in Chicago.

Hope this helps...
P.S. I still have the scars from where the fox bit me when something frightened him, I was handling him to try to get him used to people again so he could be adopted/resold as a pet. I took responsibility for the bite, otherwise he would have been put down.
Apparently they don't make a rabies vaccine for foxes, which is why they have to be killed if they bite some one.

Carol