Previously purchased songs not appearing in iTunes?

Over the years I've purchased quite a few songs on iTunes, but a while back I lost my iPod. Recently I've gotten an iPhone so I was going to put those songs on my iPhone, but when I checked all my music wasn't in iTunes. I checked "Music", "Purchased", "Check for Available Downloads", and even went looking for the music files on my computer, but still not all of my purchased music is showing up. When I go to "View My Account" and look at my purchase history it shows every song I've downloaded though, is there any way I can get all those songs back into iTunes?