Aegir drupal hosting services
Picking Drupal hosting can be a daunting task if you aren't sure what is available to you. In some cases, you might be fine with something like a shared hosting environment that Hostgator or similar services provide. In other cases, you may need a good VPS like Slicehost or Linode. As the site continues to grow you might even look into managed Drupal hosting with more power to handle you or your client's website such as Omega8.cc.
As the need for more computer horsepower to drive your Drupal site increases, so will your need to learn what is the best hosting environment for your particular application. This will save you a lot of extra money in the long run from your hosting company, as in most cases you just need to learn how to scale your Drupal hosting environment to fit your Drupal website's needs. In some cases, Apache Web Server might still do, but in many cases these days, you can get away with a much lighter memory footprint and faster access times by using NginX. You can achieve even faster speeds by bundling NginX with other PHP enhancements like APC, Memcached, and faster implementations of PHP for NginX like PHP-FPM. Apache was designed for huge enterprise website applications and will scale almost infinitely, which is not good if you only have 512MB of RAM on your VPS server. That is where NginX comes in. You can run just as many pageviews with a much smaller memory footprint, and with PHP-FPM it manages itself much better than Apache's Worker Process Manager.
Another great hosting tool that you will want to get yourself familiar with if you are going to be a power Drupal website administrator is the Aegir Hosting System. Aegir will allow you to deploy Drupal sites within specified platforms that you upload to your server. Each site is automatically installed into a Drupal multisite installation and the whole server instance is designed to be managed by Drush. Beyond that, you can migrate sites into other platforms, clone an existing site to another domain, and disable sites and platforms so they can't be used any longer, but can be restored later. it is quite awesome once you get Aegir setup, which is why I am able to easily maintain my 10 site Drupal multisite installation. I used to have a mulstisite installation setup before Aeigr, but with Aegir managing the whole mulstisite instance is much easier.
Omega8.cc has actually created a Git repository that is from what I can tell, the exact script they use to install new client Aegir hosting installations. It is probably the easiest way to get an Aegir instance up and running and is optimized to the brim.
Grab The NginX for Drupal installation Script off of GitHub. There are now 2 installation scripts that run which make updating the Aegir installation a lot easier than it used to be. The Omega8.cc installation script configures the fastest Drupal environment I have ever experienced, and I constantly have people I show the speed tell me the same thing.
Quality Drupal Hosting Services
Acquia.com - Managed Drupal Cloud Hosting
Linode.com - Drupal VPS Hosting. Linode has Stackscripts which will allow you to install a fully optimized Drupal installation in minutes.
Omega8.cc - High Performance Managed Aegir Hosting. They now offer SSD hosting plans which add even more speed to this highly optimized Drupal hosting service.
Pantheon - Finally realized. I have been testing the beta for a while, and it's quite a nice hosting service for serious Drupal developers.
Buzzr - Drupal Hosting as a Service. Designed to compete with Blogger and hosted Wordpress solutions.
Drupal Gardens - Another Acquia hosted solution. This one is similar to that of Buzzr where they provide Drupal hosting as a service. Drupal gardens however has a free account.
Drupal Hosting Services Worth Checking Out
BinaryCPU.com - Very competitively priced VPS plans available in Chicago.
HotDrupal.com - Hot Drupal offers high memory and data availability vs. high storage and bandwidth capacity. Their servers run SSD hard drives, so you can be sure they are blazing fast.
DrupalCentric.com - Competitively priced Drupal optimized VPS hosting plans
Try reading some of our Drupal Hosting Reviews to get a better idea of what service you may want to use.