For now, it looks like I'll have to buy a new iPod.
The thing is, I was fully satisfied with my Classic iPod with 80 Gb: I'm using around 50 Gb of it...
This means I don't want a crappy 34 Gb shit, just like I don't want the fatass 180 Gb or even 120 Gb... I want a goddamn 80 Gb!
... but it looks like Apple decided for me that 80 Gb would never be enough, nor would 120 be!

Where can I find -new- 80 Gb iPods?

http://www.newegg.com/Product/Product.aspx?Item=N82E16855125071&cm_re=sansa-_-55-125-071-_-Product
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=micro+sdhc+32&x=0&y=0
http://www.rockbox.org/

http://www.iresq.com/ipod-classic-80gb-hard-drive.html

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=ipod+80+gb&x=0&y=0

I'll just note that I recommend looking at Zunes as well. I've been very happy with my two zunes (120gb and 32GB HD), and the software that comes with Zune is much faster than itunes and much sexier than it. Just take a look.

This link looks like it is perfect. If I understood well, it's just a brand new Hard Drive, which I will have to install by myself?
Is it 100% safe to buy-online? And am I sure I'll get what I want? I don't know the site's reliance at all...

I ordered a screen from there after I went to a mac store and asked them for a screen. They said to order from iresq, since to replace the screen you need to buy a new hard drive and internal components as well for $180.

When i got the screen, the only problem was that it was out of the anti-static bag. I sent them a message explaining this, they apologized and took a note of it.

How to make sure the thing will be 100% compatible? I mean, Classics have Generations... could it interfere?
I just really don't want to pay 120$ for something that won't work.

If you're worried, open up the ipod and check the SKU. Otherwise there's a 30 day refund policy.

To get most of the stuff out of the ipod, there's little tiny levers/tabs. Some of them are black, some of them are brown, some of them are white. Look extremely carefully for each.