(This questions was asked in an earlier task, but we're asking this again just in case you need to change it because you couldn't find a good web domain name for your startup)
The domain name name should be meaningful to your business. Nowadays most shorter domain names are not available, especially for domains ending with .com, so it's really hard to find something that's good. A good domain name is often a synonym of the keywords you are thinking about, or it could be names that sound like the keyword you are looking for. A combination of words is also quite good, but make sure to keep your domain at 2 words max.
Case Study: Google wanted Googol, but they got Google because Googol was already registered.
Also, nowadays it's very popular to add prefix words like "join", "get", "team" or suffixes like "app" after the domain just because good domains are hard to come by.
Examples: joingrouper.com, bufferapp.com, getpocket.com
.com domains are the most popular, and the .net is a pretty distant second. However, there have also been a lot of companies who use country domain suffixes to complete their domains.
Examples: delicio.us, or something like bit.ly.
.co suffixes are very popular recently for new-age startups, so that's great too.
.io suffixes are pretty popular too, especially for geek-friendly websites!
Jason Calacanis's advice on domain names:
https://launch.co/blog/how-to-name-your-startup-and-land-the-perfect-domain.html
Places to register your domains (and to host your website):
If you plan to host your website at a shared host (cheapest at around $2/month and the easiest to set up), a lot of them also give you a domain name for free for the first year. The options below are the most popular options:
iPage, JustHost, GoDaddy, Gandi (no bullshit!), Fatcow, WebHostingHub, BlueHost, InMotion, GreenGeeks, HostGator, HostMonster, Namecheap, CrazyDomains
You can also use whois.net to find out who a domain is registered under, in case if you really really want it and want to acquire it from the owner.
Websites to find good domain names:
http://www.visualthesaurus.com/ (good to visualize alternative keywords) - Use it to find synonms to your keywords
Spend maximum 15 minutes on this. This is not important for now since we will need to validate your business idea first.
Also read: How to Name Your Startup