I agree with much said here… If you want to rank, at least to some degree you have to be active in linking back to your site. The key is to not over do it, and know a little goes a long way… Forum sig. is a good start, Q and A sites that cite sources is another. A few good articles with back links on other websites and maybe a “shout-out” from a friends site.. I see nothing wrong with those, as well as a good profile of social backlinks as you should be doing some sort of promoting if you own a business.
Mix that with some strong content deserving of the above links… and you should be alright.