I just moved from Sitka, AK. I took the ferry to Bellingham. From Sitka to Bellingham, the cost was about $600 per car (under 16 feet), driver is included. If you get a stateroom, the price increases, I think about $150-250, depending on whether you get a 2 room or 4 room. As far as going to Homer, I imagine it would be significantly more, say $200-300 per car, and say another $100 for the stateroom. However, it is actually a really nice trip, and you get to see a lot of Southeast Alaska. Those of us who lived along the route called it the poor man's cruise ship.
Something else, you are supposed to check your firearms when you board. I actually didn't realize this until after the trip...whoops. They have a locker they'll put your firearms in.
On board, there's several amenities. There's a gift shop, a restaurant (actually, pretty nice, considering), a "snack bar" that is basically a short order style restaurant. They have a theater room where they'll play movies. There's even a bar on board.
If you can't make it all the way to Homer (from Haines or Skagway, you'll still have to go through Canada), your best bet, I think is to find an FFL in Anchorage, and have your guns shipped there. Call around, and find one that will give you the best deal. Is this a temporary thing, like you'll only be there a few years? If so, it might be worth while to be selective of which firearms you want to bring with you, and leave the rest with friends or family in the "Lower 48" (a term that will become very familiar to you in Alaska) that you trust. Anyway, hope this helps.