All of the above advice is very good, and if you go on www.doctorjob.com it has some very good advice on how to put together a good curriculm vitae. If you join an agency, they will ask for your cv, and when you register will talk to you about your skills, and like Kim A says, think about how you can translate your life skills and experience into skills an employer would be looking for. Also, I know that volunteering doesnt sound amazing as obviously you dont get paid, but if your not working now, its the perfect time to do it, and the experience you will get from that will help in developing your cv, plus, prospective employers will be really impressed that you put effort in working for free.
Good luck, and keep positive, I have recently struggled to find work and kept getting rejected, its disheartning I know, but if you keep trying and apply for everything, and join a couple of agencies that will look for you too, something will turn up I promise! x