I was wondering if anyone could suggest me a setup for my computer, be it just regular computer speakers or some sort of setup that interfaces with bookshelf speakers.

Although I'm rather experienced with headphones, I'm a complete newbie when it comes to speakers.
I would like to spend around $300 USD, or at most $400, for setup.

Of course, if I don't need to spend that much to get what I want, that's even better.
Type of sound that I like:
Relatively tight if possible, fast, decent extension both low and high, great soundstage and imaging. Extreme bass is not required.
What I want to do:
Enjoy music.
Movies and games are not important.
Music types:
- JPop / JRock
- Trance / Ambiance / Trance+Vocals
- Classical
- Instrumental Rock (Apocalyptica)
- Thematic Choir and Gothic (Lord of the Rings, Gladiator, The Patriot, Batman Begins, etc.)
- Industrial (Rammstein)
- Rock and other stuff: Evanescence, Linkin Park style stuff
All I have so far:
EMU1212m soundcard
Source files: EAC ripped -> Maxed Quality FLAC encoded
Thanks soooooo much everyone!
Cheers,
Venio