It is possible to buy 2 domain names from godaddy and point them to the same website? I already have a domain name with godaddy is linked to my website that is hosted at hostgator. If I buy another domain name from godaddy can I just change the nameservers to the host gator name servers(like i did for my first domain name) and will it go to my website or is it only possible to have one domain name pointing to my website instead of 2?
It is possible. Change the 2nd GoDaddy domain to your Host Gator nameservers, then goto cPanel or whatever you use and add an additional domain and have it redirect to the 1st domain.
Does your Hostgator plan supports Parked Domains ? if so, you can add the second domain name to the site then at GoDaddy just point the DNS to Hostgator DNS Servers and it would be done.
You run a risk of getting banned if you point two domains to the same website. The correct way to do it is to do a 301 redirect from one domain to the other.