I totally feel you on the nostalgia, I used to love customizing my Winamp back in the day. I've been digging around and it seems like those old transparent glass skins are still floating around online, you just have to know where to look. I found a few websites that still host some of the classic skins, including the transparent ones, you can try searching for "winamp glass skin" or "winamp transparent skin" and see what comes up. You might also want to check out some of the old Winamp forums or communities, they usually have archives of user-created skins that you can download.