FC Halifax Town Programmes have a "Lucky Programme Number" on the frontpage, I presume there will be a draw with a prize, wouldn't have to be a massive prize but could provide an incentive, may be able to get a local company to provide the prize each week with some advertising space in the programme in return.
An alternative way of doing that which doesnt need any additonal printing on the front page (lucky number bit) is to do what Manchester Phoenix do, in their programmes if your Dominoes Pizza advert has a signature on it (store manager signs a set number of programmes before they go on sale) you get a free Pizza, they go as far as to deliver it to you at the game!
Something along those lines may help increase sales if their is a chance of winning something.