Very new to SEO and wondering if I am wasting my time/money on something that is not possible.   The top 3-5 keywords I want to place have top results offered by a .gov, wikipedia article (title is my keyword) and about.com.

My gut tells me that I could work my tail off for the next few years creating content and links and never be able to out rank these sites so I might be better off just buying ads for those terms.   Before I make any decisions I wanted to get some perspective from the experts.

Thanks!