There are a number of good third party ticket vendors who sell discounted tickets, however most of them will get you a discount on multiple days, and not really just a 1 day ticket. Are you in the military, a florida resident, or anything like that?
There is not much you can do for a 1 day ticket. On occasion you will find a coupon for a discount (eg Bring in a can of Coke), but most discounted sellers only deal with multiple day tickets.