My in-laws are wanting to take a dream trip to Alaska for their 40th anniversary and I'm trying to help them make it a possibility using miles and points where possible. They have no reward cards and no loyalty memberships right now, but they're willing to get them. We also have some time - they are looking to go between June and August 2013. They will be traveling from Des Moines (DSM).

I'm thinking AA miles to get them from DSM-ANC, but please tell me if there's a better way. They want to do a short land tour first, either on their own or possibly a guided thing. They want to take a train up to Denali Nat'l Park and hang out there for 2-3 days and then take the cruise. So a RT cruise from SEA or YVR doesn't work so well. It needs to be a OW south-bound itinerary; they can fly home to DSM from wherever.

Any ideas on how to leverage miles/points to help them out beyond just getting free flights?