Comment 59 for bug 569601

I've carefully followed the instructions at #27 and #44 but I can't get past the 'unpack' bit at bullet 4.
Whether I'm in the first directory of the terminal or the directory containing those downloaded files, I just get:
dpkg-source: error: can't open gnome-pilot_2.32.0-1.dsc: No such file or directory.
What am I doing wrong? (I'm not familiar with unpacking, building, etc).