Where can you find English dubbed versions of xxxHolic online for free?
Try veoh.com. onemanga.com is only the comics, not the shows
You can find many English versions online, go to an anime site and they will often have English dubbed versions, if you want to download them, try using rapidshare or mediafire as those are generally filtered within reason. Due to infringement many of these will get deleted whether it is the video or the download. So posting a link here would be of little importance.