Those who know me and how I feel about most SEO pushers know I don’t think any of these “services” are worth any money.
But that doesn’t mean I don’t think there is nothing that can be done to help your placement. It’s just that ‘Content is king’ and if you don’t have meaningful content on your site there is nothing for SEO to do.
But if you have a site that is valuable Google has a PDF book on what you can do do help it be seen and find better search placement. This is it:
It is one of the few reads I recommend for this purpose.