Unique content and contiued presence in web world like Linkedin, Hosting related forums, Posts / threads related to security, Knowledge base articles, Blog articles to the latest development and updates etc and world class24/7 suport for your customers via ticket and livechat (if possible via phone for emergency as well like server down) will be the best methods to improve your sales.
In my opinion if you have unique content , then there is no need to spend on google adwords as google will catch you automatically. But you need to spend money on basics of SEO done properly in your site.
Online presense will make customers feel that you are having a goog presense in the online world and they will defenilty check for reviews for your company in forums related to hosting and for this you need to stay active , help people as much as you can for free via these communities and forums which will be a proof for your knowledge level, work attitude , work experience, etc . You can also send / publish your offers to these forums or other online sections so that you can attract customers as well.