External Links- website

I have many many web sites, prepared over years. I connected all the web sites with links. Some link centers are prepared as the search lights. These centers will be in different domains like blogger.com, bravehost.com, geocities.com and add all your links in those pages. Each link page should have around 40 links in that page, with some content in the top. From all your other sites, connect to these centers. Whenever there is a change in the link address, you can change only in the centers.
People advice to request others for link exchange. I dont know how far this would work. It is a tedious job to search for the owners and request them. One more important thing is, without page rank also your page can appear in search results, based on some other points. In such case it is futile to waste your time and energy in obtaining the pagerank. Page rank is required only in such case where competetion is high for a particular keyword and you want to be displayed only in that keyword.
Adding your site to directories is also a big trouble for ordinary people who just need some bucks from adsense. Dmoz.org is a peculiar site. We dont know their peculiar type of operations. Inspite of your requests, they dont add your site nor reply. You will find many useless sites already added in that dmoz directory. Becoming an editor is also not possible as they mostly turn down every genuine request. So, in my opinion , it is better to be away from these directories and wipe off the notion that inclusion in the directory will fetch some thing. We get nothing but a page rank around 4. without inclusions also, just like we are getting for some sites, without evern much content. I created some useless pages in a site. They got page rank 4, 5 for a few lines. These sites can be used to act as link centers.