It seems like the demand for the two products is simply insane, lots of links do not work.
I have found a couple of links that have been pretty reliable for me so I will share them here:
- Download SharePoint 2013 here
- Download Office 2013 (aka Office 365 Preview) here
- Download Project Professional 2013 here
- Download Visio Professional 2013 here
The offie link is a little flaky, I assume due to millions of over excited downloaders.