Hostgator is one of the web hosting , that offers unlimited domain, so that we can use a single hosting account for multiple domains, until now I use hostgator for about 10 domains and so far so good.
Hosgator , it is more expensive than JustHost that provide free domain or BlueHost who also provides a free domain name and are both providing unlimited domain, but with cheaper prices. Or it could be in Hostso which provide free domain and can accommodate up to 5 domain if you taking Achieve package for $ 3/month.