Best way is to wait until you get to Florida - lots of "motels" and tourist info centres advertise discounted Disney tickets. Try a search online as well. However, I think the best you'll find is a few quid off...unless you agree to spend a weekend listening to timeshare pitches or something.
As far as I am aware Disney do not discount thier tickets, signs that you see when in Florida advertising discount this and that usually as previous posting say's are connected to time share and the Hard Sell. So you will have to pay full price, but it is worth every penny! The only trouble is too many kids!! should be only for us Big kids ;)