look here:
https://wiki.ubuntu.com/HardwareSupportComponentsSoundCards

and here:

http://www.alsa-project.org/main/index.php/Matrix:Main

via envy24 chipset ones are quite nicely supported.. but those are mostly PRO soundcards and harder to find.
M-Audio, Terratec and similar are the companies that manufacture those.

I am using Essense for creating my music tracks

http://www.asus.com/Essence_HiFi_Audio/Essence_STX_II_71/

Kernel 3.18 and up have full support for this sound card...

So Anything Xonar is 99% compatible with Linux :)

I will look at Xonar cards.
Essence is too much for my needs. I want a sound card just for a headset and some small speakers.
Thanks for your replies guys!

Regards,
PUN

I am currently using a cheapo DeLOCK Sound 7.1 USB soundcard. It works on Linux out of the box, but only appears as a stereo device, so surround doesn't work. The store I bought it from even advertised Linux support.

If you buy a Xonar card, just make sure you're running the latest Pulseaudio (> 4.0) as you might run into problems like I did with my Xonar D2X (now it's just laying on a shelf).

https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/598308

Not a big deal, but hell of an annoying bug.

I've got an Asus Xonar DX 7.1 internal card that works pretty nicely. It doesn't have the GUI program like in Windows, but you can control most of the volumes via alsamixer in a terminal (plus there's always other programs on Linux that will let you do nifty things like set the sound to feel like you're in a studio or in an opera house, I've tried them).

I've been using it for 2 years, it's solid. Definitely increases the bass on Ubuntu by a lot. The sharp treble sounds are the same across Windows and Ubuntu. Overall, it's better than the on-board Realtek sound I have ( which is "5.1" ). You will need a free PCI slot available on your motherboard to fit this baby in :)