For speakers, Corsair SP2500 is really great! Check out Tom's review on them, they will really blow your mind!
As for a sound card, if you're looking for something really good, some guys in here will probably recommend something for you, when I bought the SP2500's I just figured anything other than the onboard audio card will be good, so I bought a fairly cheap Asus Xonar DS.. Very pleased with it, noticed a big difference in music, games and movies with my headset, and the audio in the speakers are really nice...
Consider it, for me it was one of the best purchases I have made for a really long time, I use it all the time.
i7 950 @ 4.0GHz | Noctua NH-D14 | GA-X58A-UD3R | 2x 5850 Crossfire | Corsair DDR3 6GB, 1600Mhz | Silverstone Raven 2
X2 240 @ 2.8GHz | Noctua C12P SE-14 | MSI K9A2GM-V3 | HD 5750 | Kingston 4GB | Antec 300 White