In reply to goldmember: Quite specific to the 'Monster' sites etc I'd say that I had a professional CV writer look at my CV and his comment was that if I were to put it on internet sites, it needs to mention keywords as much as possible because in the searches done by employers, THEIR key words are what generates the replies. So for instance instead of just saying you have completed the Prince 2 project management course, you'll say things such as 'implemented blah blah using Prince 2 methodology a couple of times which would increase your strike rate.
Not related to websites, it's handy to talk to people you know/knew to see what's going on.
For instance in construction, there's little going on in the resdiential market, but commercial and particularly retail are doing well, so check, do you have the right qualification for what is current in your inudstry? If not, get on a government funded course. If you look hard enough, there's usually funding for anything if you're unemployed if you can prove it's relevence.
Tailor your CV to each application where possible.
Make your cover letter clear and concise. The presentation of the cover letter says as much as the letter itself.
Above all, don't lose heart. Dedicate an amount of time each day or every other day just spent looking at ads and replying to them. You can save off various versions of your CV as you adjust them ( no lying, just emphasising different points, lies will usually be found out in a good interview). That way you're not constantly re writing the whole thing.
Lastly, get some low paid cash work, I don't think many would begrudge that to someone who is trying hard to find work and use the dosh to get into a hobby cheaply, such as climbing or sailing, so when you look back at your time off, you have good things to look back at!