i'm in the middle of fundraising for a charity trek, for our local hospital.
the things to go for are those with little effort and big rewards,
have you a registered charity number.
the biggest fund raisers so far are bed push around town (@£600) for 2 1/2 hours
quiz night £800 (charge entry fee to pub/club incl food, £5 per team for quiz and have raffle)
also local football club; ask to stand outside(on their ground) with collection tins again alot of money for little expenditure

good luck