From the Team Automattic (who made WordPress, Jetpack, and products empowering half of the web), LeanDomainSearch is an amazing tool to find your favorite domain name and its availability on the web.
Since most of the popular domain names are already occupied and some of them are very costly to afford as a new business, LeanDomainSearch is a vital tool (which is even free) to find if your domain is available for registration or not. And if not, what are some other names you can choose.
The interface is very simple. You only need to put the word which you are planning to add into your domain it LeanDomainSearch will come up with the thousands of domain name ideas you can use to build your next website. Availability of the domain name will be shown by the color of the area. For example, green is for available.