Please help me write a covering letter and C.V.

I have been out of work for quite a while due to looking after my family (I live in the UK), however I am quite eager to find work. I am finding it impossible to even get an interview let alone anything else. I think it may be due to my C.V. and covering letter. I have been a full time Mum and although I have taken and passed my ECDL and learnt a foreign language this has been over 7 years, the rest of the time has been spent looking after my family. I have done some voluntary work in a retail shop and helped out on school trips too. I’m just finding it very difficult to put something together that is going to catch an employers eye (especially in this economic climate). Does anyone have any cool tips or templates I could possibly look at? I am looking for office work and something which may fit in with my child’s school hours (childcare is impossibly expensive here too). I fear that putting down that I can only do school hours may be off-putting and putting down that I have been a full time mum doesn’t look right either. Any help is appreciated.

Thanks in advance.