vi /etc/resolv.conf

domain myhealthcare.com
search localhost 
nameserver 127.0.0.1
nameserver 72.34.255.211 
nameserver 64.182.250.130
# dig google.com

/etc/network/interfaces

# dns-* options are implemented by the resolvconf package, if installed
dns-nameservers 64.182.250.130 66.34.224.254 
dns-search myhealthcare.com

sudo apt-get install dnsmasq
    vi /etc/dnsmasq.conf

listen-address=127.0.0.1
vi /etc/dhcp3/dhclient.conf
prepend domain-name-servers 127.0.0.1;
vi /etc/resolv.conf

search yourisp.com
nameserver 127.0.0.1
nameserver xxx.xxx.xxx.xxx
sudo /etc/init.d/dnsmasq restart
dig google.com

-= REMOVE =-
apt-get remove --purge dnsmasq
apt-get clean

Reference: http://embraceubuntu.com/2006/08/02/local-dns-cache-for-faster-browsing/