Q: how to add content to my website

Are you able to open your old site in iWeb?

Find your domain.sites2 file, which will be under your User Library/Application Support/iWeb/domain.sites2.  Double click on this domain file and iWeb should open your website.

You also need to remember that in Yosemite your User Library is not visible, so to make it visible, click on the Go menu in Finder and then hold down the 'alt' key and your User Library will become visible.

Also, if you have more than one domain file, then you can only open the first one - Yosemite will not allow you to open more than one domain.sites file after you have opened 2.

Other than this and if you can't remember how to use iWeb as it has been so long, then don't use iWeb at all.

iWeb is NO LONGER a supported product and has not been sold or supported by Apple for over 2 years now.  Check out the alternatives and use one of these.

There are many to choose from, so go and check out RapidWeaver, Sandvox, Freeway Pro/Express 7, Flux V, WebAcappella 4 and EverWeb.

From this list, you should be able to find something that suits you.

Your iWeb folder is in the Application Support folder of your User Library and NOT your System Library.  Look in your User Library, as I stated in my post and you will find it there and follow the instructions posted to ensure that your User Library is visible - Click on Go in the Finder and click the 'alt' key and your User Library will show up.

Also, none of the applications listed have import facilities, so it will means re-building your site from scratch.  The only applications that do have import facilities are DreamWeaver and Flux V, but they both have a very steep learning curve and unless you know html and css you may not get on with these.  Also, iWeb code does not import well, so you are better off starting from scratch.

Take a look at EverWeb - this is very like iWeb and you can re-build your site by dropping and dragging.

You're looking  in the wrong Liberia.  You want the Macintosh HD/Utenti/Your-Name/Liberia folder.

It's very important to read the instructions :

"click on the Go menu in Finder and then hold down the 'alt' key and your User Library will become visible."

And if you have access to the interwebs, you can search for the answer :

http://www.google.com/search?q=os+x+library+folder+not+visible

NOTE: In Lion and Mountain Lion the Home/Library folder is now invisible. To make it permanently visible enter the following in the Terminal application window: chflags nohidden ~/Library and press the Return key - 10.7: Un-hide the User Library folder.

 

For  Mavericks and Yosemite  go to your Home folder and use the View ➙ Show View Options menu to bring up this window:

After you do the above you'll be able to search your simonelombardi/Applications Support folder for the iWeb folder.

Since you're going to have to start over from the beginning you should think about switching to a modern, web development application.  iWeb has been discontinued for over 2 years.

One app that many have migrated to is EverWeb because it was designed to be very similar in appearance and function to iWeb but with more up to date features.

You can copy an paste text and images from your currently published site into Everweb when rebuilding the site. There's a demo version you can use to see if it will work for you.