Yes, it's expensive. But the solving is depended by that what sound you want.
If you will use the headphones, you must to know that all modern built-in soundsystems and linear outputs of seperate soundcards are not able to work with low resistance of headphones and an additional amplifier may be required. And using headphones you may not to differ Audigy and built-in or other low-quality soundcard.
Different people have different representation about sound quality. As I wrote above Audigy is the good choice for hight quality sound. But the good quality acoustic systems are also needed or separate sound center with digital input. But the total system cost will be extremely high.
If the sound capabilities are not critical for the system, some cheap soundcards may be used. Examples are (if Creative) SB 128 Compact PCI, VIBRA, PCI128, soundcards with chips Yamaha-754, Crystal CS4281, CMI8738. Some of these are integrated on new motherboards. But the better idea may be Creative Live!.