I have only a laptop too, and (thanks to people on this forum and some other places as well) I found an outstanding quality PCMCIA Type-II sound card for laptops, the
Echo Indigo. It's $129.95, and has clearly better sound quality than the other adapters I've owned (Yamaha AC-XG, some Creative SB models, MX200 and MX 300 [Aureal Vortex II-based] cards). I haven't done blind testing on them (wouldn't know how), but at the very least I'm sure I could pick out the transient-crackles and no-signal-hiss as any of the others (they all did this to varying degrees...drove me nuts) and the transients-with-no-crackle and no-signal-silence and as the Indigo.
The integrated headphone amp is nice and powerful, too. At the same time I bought the Indigo I also got a seperate Xin headphone amp, but it was almost unnecessary since the Indigo card by itself can cleanly drive my Grado headphones or my Sony plugs louder than I'd ever want to listen to them. Even playing a DVD-based movie on my PC, I pipe out the video to my TV but I prefer the Indigo to output the sound directly to my Klipsch speaker system.
Here are some of the stats on the Indigo...
- Greater than 111dB Dynamic Range (A-weighted)
- Better than 0.003% THD+n @ -3dBFS, 1 Vrms output level
- Frequency response of 10Hz – 22kHz, ±0.25dBFor $99.95 more, they'll throw in a pair of Sennheiser HD 280 Pros (which are a-l-m-o-s-t as good as my Grado SR-80s

), and for $29.95 they'll add a copy of InterVideo WinDVD (which I had been using long before I got my Indigo...great program!)
Just thought I'd mention this card as an option since you seemed to be ruling out the laptop as a part of your hi-fi system for lack of a good DAC solution to use with it. My laptop is the center of my hi-fi system, and for the combination of sound quality, features and convenience it sure beats my Sony non-ES component stack any day of the week!
Something to consider...
Edit: Clarifications...