While there are currently over 85 retailers that can sell .eco domain names, there are some domain registrars that do not yet carry .eco. If you search on those registrars, you may see a message saying that the name that you're looking for is unavailable.
What the registrar is really saying is that they do not carry .eco domains - not that the domain has already been registered.
We also maintain a list of approved .eco retailers - including those that are working to minimize their environmental footprint - so you can choose where to buy your .eco domain name based on your criteria.
If there are domain retailers that you would like to see carry .eco but currently don't, please let us know at email@example.com. We are working hard to ensure that as many places sell .eco as possible.