Hard problem what anybody face at the time of link exchange if you don't have page rank on your proposed link page. 80% link requests get trashed because of "no pr" or "low pr'. After directory submission, Blog submission waits for next Google PR update. You'll surely get pr 3-4 if you have 100-150 link backs. Now when you have good Pr then start link building for your site. If you are going to propose a well established site be sure you linked back the site first. Otherwise they may reject your proposal. The process I'm discussing here is actually 3 way - for your site A you are proposing a link back to site B from your site C. So this is 3 way link building. This kind of link building is hard to get detected by search engines because they can't find a clue. But remember you should host your site C on a different server with different ip. For this different server and ip factor search engines can't detect the link.

Search engines now understand that both sites have mutually agreed to show each others link to gain link popularity. But in case of one way it can't trace a link back. That's why it gives more value to those one way links. Why one way links are important? Think of a situation: can you ask Google.com or yahoo.com to place your link on their home page? No, if you even do they'll not place your link. But many web sites place a link of Google/ yahoo/ msn on their page. That creates the one way link for those domains. They are doing nothing to get a link back. When a site continues to get more and more one way links then search engines also start to think that the domain must be important so other sites are linking back