A good place to start would probably be http://www.hard2hire.com if you haven't checked there. They specialize in jobs for people with a criminal record and they have listings of what employers will accept so you know before you even apply.
Here is a link that might be of help to you.
http://www.dcejc.org/app/docs/crim-rec-wash-post%5B1%5D.pdf It's an article in the Washington Post. It was written in 2002 but it contains some very helpful info.
Most companies today do background checks. You may need to find a company that doesn't do a background check just to get your foot in the door and gain some experience. Many of the trades like carpentry, or plumbing that are smaller contractors don't do background checks yet. They are costly. Once you get your foot in the door, put your criminal past behind you and start your new life.
I find it very hard to find a job with a background check. I committed a felony in 2005 at the age of 18 and I have been paying for it ever since. I written a blog about this topic. This might help you as well. http://www.exfelongirl.com/
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