Hmm… It seems that it is not reading miniseed format files as well. I have 0.8.4, the newest version, and the obspy folder that contains arclink,core, datamark, db, etc., is located here:
Judging from your Error traceback, I strongly suspect this is an issue
coming from a broken installation. You can try to run the Obspy test
suite and report the results, I suspect there will be plenty errors.
I think you have to go back to installation instructions, there must
have gone something wrong I think.