There aren't a lot of coupons available for cruise ship port touring. The coupon books, Toursaver and Northern Lights have the bulk of their coupons for interior Alaska. Are you touring there??
You will need to check both when they come out for 2010 offers later fall and see what is in them this season. The only significant coupons that were mentioned this season, for cruise only travelers, was a whale watch and tram.