Search Engine optimisation also known as SEO has changed dramatically over the last 5 years, it really seems to have gone around in a big circle as to who you would use to create your campaigns.
In my opinion (backed by 12 years of facts), you need a four pronged approach, Start with optimising your website, make sure it has the right message to convert into sales, in the past, techniques to get high rankings failed to do this and had a negative effect on visitors creating a false economy, being number 1 on the search but with no conversions or sales.
Then set up a social media campaign following your brands guidelines (if you don't have any create some) using call to action banners and buttons.
Target local businesses first, don't sell at them, engage with them, join local groups and networks. Social Media is the buzz word at the moment but dont rush in, Twitter and Facebook are the most popular but not always the most effective. Have a look at Linked in , this is a business "Facebook" and can be very good for B2B sales.
Look outside the box, If your retailing you can use Pinterest or Instagram to promote images of products. there are social media platforms out there that are industry persific, have a look for these also.
Thirdly you need to get creative! Write about your product, the more the merrier, content is king. make it interesting and informative, this content is the starting point for your SEO campaign. by now you should have a few connections locally from your social media campaign, and them to promote your content in return, you do the same.This is Search engine optimisation and this will create links to your website which is still a very big factor in ranking on Google.
Internet marketing is were people who think they know our businesses and have no clue look at me funny!
This is often miss represented as SEO, Internet marketing is Visual online marketing, let me give you an example, Group-On, they use Internet Marketing, you will probably have been on a weekend break with Group-On but you will not find them at the top of Google, or even in the top 10 for the term Weekend break. the promotion of banner ads, emails, apps are the key to this area.