Dealing with ADHD and not able to hold a job.

I need some information, some direction on what to do concerning how to keep a job or a place that offers jobs to people dealing with this mental disability. I have been diagnosed with ADHD. I have tried to keep several jobs and I am now 27, and still I have not been able to hold a job. Because of this problem every job I have had (which is always very short) doesn't last and it shows when I am trying to apply for a job. So who do I need to talk with to get help with getting and keeping a job? Please help me if you can thanks!