Q: after buying a new laptop. i've lost all purchases and my entire library

Hi walkinstyk,

There are a number of methods you can use for transferring your music library from an old to a new computer. See this article -

iTunes: How to move your music to a new computer

http://support.apple.com/kb/HT4527

Note that music purchased from the iTunes store can be downloaded again at no cost, provided it is still available on the store -

Download past purchases

http://support.apple.com/kb/HT2519

Thanks for using Apple Support Communities.

Best,

Brett L