I don't have a sound card either so is it worth buying a 20$ sound card with the new speakers? Do the cheap ones really make that much of a difference? I love my music to sound good, but I'm not an audiophile by a long stretch. I just like deep bass and clear/sharp trebles, and being able to play said music relatively loudly without the speakers making the static noises.
The difference between internal mobo sound and cheap sound cards is pretty negligible these days. When it comes to speakers, for consumer stuff I don't think it really matters much either because your room acoustics will be a real bottleneck for sound quality if it's not treated.
An Asus Xonar DGX is a decent sound card and cheap, if you have a decent Z87 motherboard the sound quality is about the same but in-line mic sound is better with the sound card. Older motherboards are probably slightly worse again depending on which you have.
question for the americans, whats with the insane prices on amps and bookshelf speakers over there? its not even equivalent to sterling prices, would love to recommend stuff like the wharfedale diamond 9.0 since they are amazing for the price, but that doesnt seem to exist on amazon.com, and everything else is at a premium, whats up with that?
Your best options are either the Z623 mentioned above, or if you can find a used Klipsch Pro Media 2.1 setup off eBay that would also be very good. As far as buying a separate sound card you'll likely be wasting your money. Modern on board sound has come quite far, you likely wouldn't be able to hear the difference especially using a budget 2.1 setup.