Need help choosing.

i know very little about sound cards, but i am looking to buy one soon. i would like to spend no more than 300CAD. i need 3.5mm input/output ports to connect multiple inputs to one or more outputs. RCA inputs are also important. i would like to be able to mix the various audio inputs into one output (speakers or headphones), and also to have it output all the same to two diff devices (as before). would be nice to also restrict and/or switch one or more inputs to a specific output. seperate volume control for diff devices would also be nice. other input types could also come in useful down the line. and, of course, good sound quality is desired, though i do not have surround sound or anything, ..not yet anyway.

specs.
MOBO: GIGABYTE UD3 P67A-UD7-B3.
CPU: intel core i7-2600K.
VGA: MSI N580GTX Twin Frozr 2

so. which sound cards should i be looking at?

Sound is a subjective matter I suggest you buy one of the tunable cards from Asus or Creative.
that way you will be able to fine tune the sound to what you like
retail approximately 190$