I followed the steps in that thread exactly.
I even copy/pasted the commands, yet it doesn't work. Is there a specific place I have to look for the sparsebundle it creates?
In Terminal, after I press enter on the third command, it just makes it like I opened Terminal new except with the previous commands on top.
When I say "exactly", make sure you substitute your names for devices, user, directory etc in place of the examples such as "Magpie".
Also, in terminal, a common error (including me) is mistaking the "$" as something to enter, it is actually Terminal's prompt. Also, I don't think any command has a fullstop at the end, pretty sure this is just punctuation to end the sentence.
The sparsebundle is created in the user's root directory.
I just had another look at the page and the way it renders to me (at work on a Windows machine tried IE8 & Firefox), the videos on RHS seem to obstruct at least one of the instructions. The command for step 3 should read:
$ hdiutil create -size 140g -fs HFS+J -volname "Backup of magpie" magpie_0016cbaf91d7.sparsebundle
I found that printing to PDF solved it, printing direct to a printer didn't work for me.
Keep experimenting, it really does work.