Naija Town Square - A Forum For Nigerians At Home and Diaspora

I'm looking for suggestions for building backlinks as well as Search engine optimization.  I worked with some providers a short time ago and have recently been unhappy.  Can anyone have any recommendations for established providers?  The particular link builder I have been recently considering is DiamondLinks.net, they're a complete link building company.  Right now they are the perfect but I needed to verify if anyone knows anyone better.