betterbidding.com is a great guide if you use Priceline or Hotwire. It will break down all the Express deals for both sites, and guarantees that your hotel will be one of 4 listed on their site. It also has a pretty good guess (not guaranteed) as to which 1 of the 4 that particular offer applies to.
betterbidding.com also has a lot of useful tips and tricks for Hotwire & Priceline. For example, none of the Universal Orlando resorts offer free parking, so if you see "Free Parking" as a hotel feature, you can be sure it's not a Universal resort.
We just booked a trip to Universal in February, & I didn't use Better Bidding because I want to be 100% CERTAIN to stay at a Universal property. I got as far as a guarantee that 2 of the 4 properties were Universal resorts, but I wasn't willing to gamble.
Aside from Priceline/Hotwire, Delta Airlines had by far the best deals on vacation packages. When you factor in the separate costs of airfare and hotel, their packages were a HUGE discount, if you're flying to Orlando.