Hi there Lucky
If you are trying to rank your website high in the search engines then as you might have heard before, you want to get high quality Page ranking websites which link back to your site. Now search engine friendly links do work some to an extent but you do not want all your links to be coming from these sites. You want different high quality sites linking back to your site. Google will then reward you for this.
Another thing about backlinks is that you want to build backlinks on a consistent basis. I usually build about 10 high quality backlinks to my sites a month. A lot of people tend do build a large number of links in a small time period and leave it. That is the wrong approach. You want to build a handful of quality backlinks every month.
A great site I have used to find high quality backlinks to link to my website is Knowem.com. This place is great because there are hundreds of high quality PR 5, 6, 7 ,8 sites you can get backlinks from. I have used this site alone to build links to my sites and I am really impressed with it.
Hope that helps