Apple has begun to eliminate websites that allow people register your UDID and install iOS 6Some American websites have removed their links to the iOS 6 betas, which is what contradicts Apple's terms.
If you have your UDID registered using a Spanish website like the one we recommend you do not have to fear, Apple is going against very important websites that sell thousands of activations, not against the little ones that are discussed here. If you have your UDID registered by any American website type instantudidactivation.com you don't have to fear either, even though they have closed and the developer accounts of its owners do not work right now if your UDID is registered they will not remove it from the database, you can continue installing the iOS 6 betas.
This access to the betas is selling for about $ 10 (on some sites for much less). If you are a developer and you are selling the slots of your account to subsidize it, be careful, Apple might shut it down for you.
More information - Tutorial: how to install iOS 6