You can always sign up with Hilton as a Hilton Rewards Member.
It is free!
And you get a better rate on the hotels.
The Hampton Inn, is a Hilton Hotel, so it works too.
Also, when you put your dates in, carefully notice on the left side, that there is an option to click, current promotion and special sales, it has an astrike * by it, if you click that option you get even better options.
I know this, because when we went to DL in June of 2013, this is exactly what we did and it was well worth it!
Its sneaky that they don't offer the best deal, you have to select it, but it is worth it.
May benefits, and free upgrades too, they send you an email monthly, but if you have a junk folder its fine!
Good luck.