laptop died with iTunes how to set up on diff computer

[JsGrandma]

The hard drive on my laptop with my iTunes died tonight and now I have to use the desktop for iTunes but it was to erase and sync my phone to this library.

I know I need to check the songs in the library that I want on my phone in iTunes but how do I get all the music that I bought thru iTunes that is on my dead laptop now onto the desktop? What about the apps that I purchased and need updating?

What is the best way to back up my phone now?