Just as I thought: it wasn't my fault.

So after leaving two voice mails at the corporate office that the HR lackey suggested might be able to help me with the invisible online paperwork, someone called me back.  She was very friendly, and she found a way I could get to the site where the paperwork is supposed to be...  But, she couldn't figure out why the link and most attachments didn't show up in the e-mail.  As it stands, she said I'd just have to complete all the rest on my first day at work.  That's what I planned on doing anyway, but it's nice that I could tell the HR lackey that someone else said so.

All this doesn't change the increasingly obvious fact that technology hates me.