~EDIT~ Also, I forgot to mention, that sometimes Disney offers discounted tickets for annual passholders. But this doesn't always happen, you may get lucky and get them discounted if you are a passholder.
The best thing to do is to check on eBay. Since the tickets are non-refundable some people are unable to go and can't get their money back for the tickets. They put them on up on eBay in hopes to get anything back.
You can also go to one of the lower priced tiers for seating. Any seat in the house is great to watch the show, so it will save you money and it doesn't make a huge difference. It will save you about $28.
Cirque du Soleil is fantastic and I highly recommend it. It is definately worth the money.
Here is some more information on it in case you don't have it: http://mousetrips.com/Cirque.html
But again, I love the show and have seen it several times. It is great the first time and just as good the times after. There is so much going on that you could see it over and over again and it will never be dissapointing.
Hope this helps! Enjoy the show ;-)