I am very undecided about the backlink building services I see all over the place... according to a few SEO books I have read building 100's of random backlinks would actually hurt your site if the websites submitting links to you weren't relevant. Is this correct? If so I am in sort of a tight spot... My website is a re-seller of energy saving products, so it would be impossible for me to advertise on my competition's websites and many informative websites. Which leads me to wanting to create a blog. Would it be better to create a new domain for the blog, or create it in my website? Subdomain? domain.com/blog?
Random backlinks won't hurt your website. Assuming you got highlighted (for some reason) on google homepage, or CNN homepage, can this hurt you because CNN and google are not related to your niche? If this could hurt, I would start putting my energies towards bringing competitors down by creating spammy sites and linking my competitors. The reason you want only quality links is because you are putting your money and efforts in getting those links. So why get a link that will not be useful. Seconly, I prefer having directory (/blog) and redirecting the sub-domain to directory (my preference keeps changing with each website I work on ) Both have some advantages and disadvantages !
Getting random links may not give you any ranking value, but it definitely cant hurt, and more links can also pull up your pagerank, though its value as far as seo and adsense is concerned is quite contentious
Building random back links will never hurt your site but if you have a relevant back links then that is weighted more by Google.