Over the years SEO has evolved into something far more than anyone could have imagined. The time where you could build links yourself and run your business is over. You need a full SEO team of people writing guest posts and submitting your site to relevant sites with good PA and history. Oh I forgot to mention making sure your keyword densities don't get too high or your keywords will drop.
There are many different ways to marketing your website nowadays, but it doesn't mean that they are all correct. Many sites are offering blog comments, forums links, pdf links, wiki links, when in fact all of them are generally spam with the occasional 1 out of 100 that aren't. These types of marketing firms are in it to make a quick buck and move on to the next person.
What to look for when picking a SEO company
Many people have come to me and asked, how do I know what to do for my site? What SEO firms can I trust to rank me up? I have a simple answer for them all. First you start with Seomoz.org which allows you to analyze your statistics and compare them with other sites. 2nd talk in the forums, ask questions, make sure you understand SEO before you start searching for a SEO firm and so you know what to expect.
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