The answers to both of your questions vary greatly.
As for fine arts careers, it depends on where your concentration is. Most schools allow (or force) you to choose a medium in which to concentrate your studies on, which may or may not be reflected in your actual degree (some schools print it, some don't), but will give you training to work in varying art fields. Some good career-oriented concentrations are Illustration, Graphic Design, and Jewelry. The key is to train yourself in marketable mediums.
Double majoring varies between schools and the majors you choose. For example, a friend of mine is double majoring in Japanese and East Asian Studies, and only needs to take an extra 2 courses to fulfil all requirements for both. I discussed with my advisor about double-majoring in Fine Arts and Japanese, and we figured out that it would pretty much be an extra 3 years of school (needless to say, I'm now only minoring in Japanese.) So if you were to double major in, say, Graphic Design and ITS or Computer Programming, it wouldn't be too much of a strain, and would put you in a good position for a job.
I also recamend looking beyond the traditional private Fine Arts Colleges, since they tend to cost an arm and a leg and have few options for academic exploration outside of the Fine Arts. I'm attending a large State University, which is allowing me to get a BFA and my minor in what will equate to about 5 years of school (counting my 2.5 years at a different University)