Oh yeah, it looks exactly like a regular headphone splitter, just that it has 3 input plugs. I have one that I use for my iPod. Good luck finding one though as they are somewhat hard to find (but I found mine at a Radioshack).
Look for a 3-to-1 adapter at Radioshack (3 female to 1 male). Plug the orange, green, and black wires from the pod into the adapter, then the other side of the adapter into your Zune.
I use a USB headset and I have no complaints whatsoever. I'm using the Plantronics GameCom Pro 1. The sound quality is top-notch, and I'm very particular about sound.
Well, from reading the title you can probably tell what I want to use these headphones for/with. I would consider myself pretty picky when it comes to sound. I also have an X-Fi XtremeMusic (but that's beside the point). My main question is I am pretty sure I will need an amp, correct? I also...
For your laptop, the sound will be pretty good but not excellent (kinda get what I'm saying?). Instead of getting that connector from Logitech, you can get an adapter from Radioshack where it's 3 to 1 meaning you can just plug a CD player or whatnot using the Z-5500's.