"that link doesn't work anymore."
It works for Windows but not Mac. Here are just-now-tested links to getting the last versions of LR 4:
4.4.1 Windows
https://download.adobe.com/pub/adobe/legacy/lightroom/win/4.x/Lightroom_4_LS11_win_4_4_1.exe
https://web.archive.org/web/20150905230858/http://download.adobe.com/pub/adobe/lightroom/win/4.x/Lightroom_4_LS11_win_4_4_1.exe
4.4.1 Mac
https://web.archive.org/web/20150906020805/http://download.adobe.com/pub/adobe/lightroom/mac/4.x/Lightroom_4_LS11_mac_4_4_1.dmg
The web.archive.org links are very slow to respond. If they fail, wait 10 minutes and try again.
Make sure you save a copy of the installer. Also, beware that you won't be able to install LR 4 on Mac OS 10.15 or later, since its installer is 32-bit and Apple dropped support of 32-bit programs in later versions of Mac OS.
Background: Dolby Labs sued Adobe a couple years ago over licensing of Dolby technology that was included in many old versions of Adobe software (including LR). In response, Adobe apparently agreed to make it difficult to download the old disputed software. And at the same time, Adobe took the opportunity to institute a new policy of only making the two most recent major versions of Creative Cloud apps available for download -- this latter policy applies to newer software that never included the disputed Dolby technology, so it was clearly instituted for Adobe's convenience, not as a result of a settlement agreement with Dolby.