I would do it
California.StateGuide.US
That would be the best way.
As for the domain, great find! Its a nice one. Especially if it is developed, who knows how much. Personally I would say the domain is a mid-high $xxx, although it is meant to be a .us it still isn't worth as much as it could have been if it were to have been a .com surprisingly. Don't think about selling it, if you feel you have enough time, I would stick to a task and develop this domain, it could really make you, and worse case senario, you sell it for a couple hundred bucks!