You could contact your local Connexions services if you havent already. There doesnt seem to be many Apprenticeships around at the moment.......
My son was in the same situation but had a back up plan and is now on an electrical installation college course. Having good GCSE results means that you can enter at Level 2 as opposed to level 1, (which would be an extra year)....... if you decided to do this then next year (say early march, April time), you could start writing to companies again but this time being well on your way to having some relevant training and experience, and by next September having that qualification too. Another year studying/learning may sound like a long time at your age, but it honestly is better to go that route than regret NOT doing it later.......
Hope this helps ;O)