Unfortunately they don't offer .ng on their website, probably still a over-the-counter thing

Hi, I represent Websoft [www.websoft.com.ng], the Registrar for Microsoft's bi.ng. The Buy-Now process of 2nd level .ng domains is on & its not over-the-counter, here is it official link by the registry published in 2010

http://www.nira.org.ng/index.php/auction

So far, The domains listed below have been registered by Websoft:

1)3m.ng 2)leadership.ng 3)google.ng 4)gmail.ng 5)youtube.ng 6)honeywell.ng 7)googli.ng 8)bi.ng