Luckily for humanity, these "social network sneakers" are concepts. For now. I fear there's no fail whale in existence that will be big enough to stop the slobbering social media masses from demanding these be created via a "Like" page.
Facebook and Twitter concepts are currently available to view, with no word, thankfully, of a retail version.
The MySpace ones don't exist yet, but you could probably create your own by scratching out Facebook and writing in MySpace with a pen.