I have a site that has hundreds of pages with unique content that target long tail, low competition keywords. Over the past few months I've collected a lot of link sources, e.g. high pagerank profile links, web 2.0 sites that allow blogs, article sites, etc. Is it a bad idea to use the same link sources (domains) to build links to each page? I know it would be better to get links from different domains, but I will eventually have thousands of pages that I will want to build links to, and I will simply run out of decent link sources. But I absolutely can't risk this site. What do you guys think?