You really just can't do it yourself, you need to contact WebAnswers and see if they would be willing to do it for you.
The problem is that they like as much content on here as they can get, so they may not want to take it off. However, if you're really convincing on your reason(s) why you want your question off, they just might do it.
I know they have the power to take stuff off, it's just whether or not they think it should be off the site.
http://www.webanswers.com/contacts.cfm

