Help! Site has Virus/Trojan!

Someone who visited my blog recently informed me that he got a trojan warning when opening the site up. I’ve been having some trouble with the dashboard recently (often, it opens, then the page goes completely blank and say “Done” in the lower left hand corner) so perhaps the trojan is the culprit. However, I have absolutely no idea how to go about finding this trojan and what the file might look like…Any suggestions would be seriously appreciated!

Here’s my site (is it be risky to visit at this point? Should I take it down until I can get this figured out?):
http://powai.info

My blog is updated and using WordPress 2.9.2

Thanks for any help you might be able to provide.