Funnily enough, I'm presently on the 'New Deal 25+' scheme (a nice compliment - 25+ when I'm 54!!!
), run by my local Jobcentre. They sent me to a 'Training' company that helps with having lots of daily newspapers, PC's for job-searching, help with composing a good-looking CV, writing application letters, interview techniques and even free stamps and envelopes etc. They even pay travel costs to the training centre and any interviews you get
They've put me on a 'Work Placement' at the same training company, but at a different branch, where I'm having a truly wonderful time, helping the tutors, filing, making the 'Induction Packs' and generally making myself useful and (hopefully) indispensable. If they don't give me a job at the end, at least I'll have lots of extra skills to update my CV with.
One thing you can try though, is to find a company that you would like to work for - and feel confident you could either do the job or quickly learn what's needed, then either write or phone and ask for a 2-4 week 'work trial'. OK, it'll mean working for that period with no pay (just your unemployment benefits + £15 if you get onto the 'New Deal' Scheme), but if you impress the boss enough, and he offers you the position full-time, it's well worth the voluntary time spent there.
Don't worry too much though, you think it's hard finding work at 17? wait until you've turned 40 it's a lot harder. Reach 50 and finding a job is like looking for hens teeth
. I've even been rejected for a job because I was 'Over Qualified'!!!