New to Linode what else should I do?

It'll probably work fine.

Remember to run updates regularly (apt-get update, then apt-get upgrade) and enable backups if your data are important to you.

My short list of "essential" things I couldn't live without includes munin and etckeeper… both of these are handy for tracking/remembering how things change over time.

Also, this is getting way off into the deep end, but you haven't heard WordPress until you've heard it in the original Klingon. Just in case you have a mysterious urge to tinker at some point.

Thank you for the article. It might be useful someday :D

I was wondering how about email though. I know I can use google apps for the email. What's the next best thing after that?

and also should I worry about installing a firewall?

For handling outgoing e-mail (stuff your server likes to send out), "apt-get install mailutils" will bootstrap everything quick and easy. (See here for more on that)

For handling incoming e-mail (you're example.com and you want to receive mail for bob@example.com), it's not as easy. Simply getting it to a state where mail arrives in a mailbox and can be picked up by a mail client is a pain, and that's without spam and virus filtering. It can be done, but outsourcing to Google or Rackspace will save a lot of time and effort.

For firewalling, sure. If you're using Ubuntu (I've kinda been assuming that already), 'ufw' is dead simple. Really just:

# ufw allow openssh
# ufw allow apache
# ufw enable
# ufw status

Yes I'm using ubuntu

Ah glad is that simple, I will try it

and also about mod_security for apache is it that important?

I'm trying to follow the guide in the library but the csr file is expired from sourceforge