What sound card and other basics?

[misscandle]

I am very new to recording using a computer. I want to record my compositions from my Korg X3 onto my computer and then add one or two tracks of vocals.
I will be using cakewalk sonar. What is the best sound card that will suit my basic needs?
Do I need any other external devices or software, especially for recording vocals. I have noticed people talking about mixers and compressors, are these external devices or software and what do they do. Please excuse my ignorance.

[Stealthtech]

The m-audio delta series cards should be right up your alley.
Perhaps the omni studio that has preamps for your mics (sort of an all in one box) reasonably priced and reliable.
www.m-audio.com

[rpe]

agree, check out m-audio products.

[misscandle]

Thanks Guys