Your odds of getting a job that would bring you to the US are pretty low. But if you are already in the US, you have a few options.
First, I'd suggest substitute teaching; it doesn't pay great, but technical types are always needed badly, and it would give you an entry point.
Second, internship or entry-level jobs may work out if they're for an organization that will eventually have a paying job up your alley.
Third, you really need to get back to school and refresh your background, if you can possibly afford it. There may even be special scholarships or funding for someone returning to school at this point in life.
The most important thing I'd stress is that you need to show that you are keeping up with the times and are eager to learn. I'm older than you, but I get along with my highly-technical colleagues because instead of thinking "I'm too old to learn all that", I am eager to learn the latest technologies and hone my expertise.
The hard part for you, I suspect, is that what you did academically is irrelevant, as is the last 20 years. It's going to be all about what you can do now, what you can contribute and what you can learn to do well that is relevant to today's world.
Use all your energy to get started on it right away. If you need to go into a new field, well, there are a number of areas of software engineering that are always short of capable people; there are especially areas of web development that involve programming that's in demand. But don't go to a community college for "web design"; that will be useless. Instead, find a way to develop websites, even if you have to do it for free for a while, just to show off skills, and focus on programming -- Java first, PHP, Ruby on Rails, etc. -- see what's in demand.
Thanks to the fear that companies have about discrimination lawsuits, if you can actually do the job, you are likely to land an interview if only as an "alternate" candidate. But you can't do it based on your past; you have to become a "now" person who is useful in 2013.
Short of that, you probably could get a job at McDonald's, or something even less desireable.