I agree, travelzoo and CruCon are where I tend to get my best deals. FYI, Travelzoo's top 20 came out a few hours ago, and they happen to have a deal on an Alaska cruise, you may want to check it out.
I've done the Alaskan cruise out of Seattle, on the NCL Pearl. Smaller ship, less nickle & diming that than the newer mega ships, and the crew is rated as one of the best of the fleet, and they took excellent care of us. If you can afford a balcony, you will certainly enjoy it for Alaska, but it's not required. We could only afford inside at the time, but we still got to see plenty of wildlife and whale watching from the various vantage points on the ship. One of the ports of call is the inside passage, and they bring in a park ranger to educate and narrate, which made that port even better. I'm a wuss w/cold, so I stayed in the nightclub and watched the view in comfort while sipping hot chocolate. Hubby went up on deck and eventually got a spot in front to snap photos. Calving is occurring much more frequently due to global warming, we saw it happen several times during our few hours in the passage. Sounds like thunder!
Keep in mind that Alaska is an awesome place to experience, but it is very expensive, even more so if you choose to do cruise excursions. Once you book, sign up for the message boards at cruise critic and find the thread for your cruise. We got lucky in that we found a few other people who were planning excursions, so we were able to join them, get better excursions for far less money. But even eating in port can be quite expensive. In Ketchikan, we were able to find the one bar in town that does not roll up the sidewalks at the end of cruise season, and it's the one all the locals eat at. Their fish & chips were better, as they used Halibut instead of Cod (if memory serves). That cruise was maybe 4 years ago, and the cost for fish n chips at lunch was $35! In another port, a "nice" dinner where we shared entrees w/two other people still cost $120/couple, and the only alcohol was one pitcher of Alaskan Pale Ale. It all adds up, our tally after the cruise was much higher than we had anticipated. Totally worth it, but it is something to consider.