Dell is a well known name in the computer space, and with Chromebooks having risen to the most popular laptops on Amazon some time ago it was no surprise that Dell should want to partner up one of their own laptops with the Google developed Chrome OS some seven months ago. The Dell Chromebook was priced at $299 when it launched but it appears that Dell has taken the availability of this item off of their main website page where you were previously able to place an order for it. The page states that the Dell Chromebook 11 can still be obtained through a "sales representative" which points to the capability of getting it only through the Chromebooks for Education channels, basically meaning that anyone looking to buy one of these for personal use as their consumer laptop doesn't have the option any longer. At least not through Dell themselves. You may be able to find a re-seller online or via ebay if you're really into this particular model of Chromebook.
This doesn't mean that we won't see any more of the Dell Chromebook 11 available for normal consumer purchase but at this current point in time if you're looking for a Chromebook to buy as your very first or second Chromebook laptop, there are other options like the upcoming new Acer Chromebook, or the recently released Samsung Chromebook 2, or even ASUS and Lenovo's first Chromebook offerings that came out not too long ago.
When and where we'll see the Dell Chromebook 11 come back is a question we don't have the answer to, but its disappearance is said to be due to the increased demand of the product and not being able to keep up, thus resulting in Dell having to apparently decide on who to make the device available to. Since they're a big supporter of the Chromebooks for Education program, they have chosen to keep the product open only to Education customers which might have been a smarter choice at this point. Chromebooks continue to rise in popularity and from a consumer standpoint, there isn't a lack of other available options when looking to buy. That's the good news. The bad news potentially is that Dell is not one of them and if you prefer Dell products over others, you're unfortunately out of luck for now.