Dunno if this is what you wanted, but here you go. Try one of these:
http://www.animelab.com/anime.manga/translate http://www.freedict.com/onldict/onldict.php http://www.csse.monash.edu.au/~jwb/wwwjdic.html
http://www.trussel.com/f_nih.htm http://www.csse.monash.edu.au/~jwb/onlinejdic.html
Romanized Japanese is often called romaji, so I did a google search on "japanese romaji translate"
Hope this helps.
