Ok install clam av in the terminal when you scan with the command clamscan it will give you a list of files scanned.
and will either say OK behind them or infected. so you should be able to tell which file is infected.
Hope that helps.
Also you may want to give avast a try I've found it very helpful. you can get it from here. http://ubuntuforums.org/showthread.php?t=1282979
you have to register it but it's free for 1 year I think. has nice interface.