I didn't see this stickied anywhere, so here goes...
When trying to install the Clean Installer I get a message saying that the ".NET Framework is not installed" on my PC, and says that I need to install it because I can continue with the Clean Installer installation.
Excuse my lack of technological know-how (I'm a PC art/multi-media major, I'm not good with the technical side ) but what exactly does this message mean? And how to I install the .NET Framework? For that matter, where do I get it?

There is a link to download NET Framework on the front page of the Clean Installer site.

Oh, heh, I didn't see that.

On problem, though... The site doesn't work. At least the download doesn't work, anyway. When I get to the Microsoft site and hit "download" I just get a screen saying "Internet Explorer cannot display the webpage". If I click the text that says "If your download does not start after 30 seconds, click this link: Start download", I get the same message.

You could always try another browser or see if your security settings are preventing the display of the page. I just went to microsoft updates and browsed available downloads for my pc, one listed was net framework 3.0.

Sometimes my browsers conflict with sites and I have to use an alternate browser. Not sure if it'll help but it's an option

Be sure your browser is updated too, to protect yourself from security issues
I saw an update in microsoft updates for that too.

Best to ya
Xts

EDIT: The faq for SimPE requires EXACTLY version 2.0 .NET framework but any versions of net framework can coexist on the same machine going by this documentation for "SimPE Installation"