My site dropped of the face of google. Advice?

Hello Warriors...first off I would like to thank everybody for the amazing wealth of information that is here. This site has been a huge help in getting started. I am new to the IM world(6 months). I created a site around the network cabling area, which is the industry I work in now. I rose from not being ranked in the top 1000 to #9 for my main keyword within a few months. I also was ranking top 100 for many other keywords. I started building a list and hope to sell some of my own info products later on, when I can assemble an ebook or two or training videos.

Anyway, about two weeks ago I suddenly dropped from #9 to not even in the top 1000 for my main keyword. I also dropped for most of my other keywords I was ranking for. I did hire a backlinking firm from elance. They were top rated but had been doing a backlink campaign for a couple of months befor this happened. So I'm not sure if that had anything to do with it. I also did some backlinking myself in forums and article submission sites. Has anyone had this happen to them recently? I checked the google webmaster forums and looked into the robots file being blocked(not that), I checked my site on google and I am still indexed so I know I haven't been banned. I read that my backlinks could possibly been downgraded? Any help would be much appreciated.

my site is networkcablingworld.com

Thanks in Advance