I am a Windows IT Administrator for my day job and I recently started a consulting company for residential and small companies. Through my consulting company I sell off-lease computers with Ubuntu pre-installed and offer Ubuntu solutions as well as the standard Windows services (antivirus, antispyware, defrag, yada yada).
I went to school to become a network support technician and was able to land a sweet job as an IT Administrator. We mostly use Windows XP for desktops and Server 2003, but I have been able to fit a Squid proxy server and a Postfix mail server (with all the works) in on a few projects. I have been using Linux for about 5 years and started using Ubuntu since it first came out and you were able to order 100 CDs if you wanted to ;).
So far I have contributed a few How To's as well as tried to help as many people as I can on the forums with Postfix, Squid, and Dans Guardian. I hope, in the near future, to setup a blog to post more tutorials as well as answer some of the basic questions that I have had to look up the answers for.