ugh. i used to absolutely adore this game. i installed it on my old computer and that one got a virus and crashed. so, i got a new computer, tried to re-install it and its asking me for the registration numbers. i lost the box and now i can't play anymore. any suggestions. =/

Unless you have used a registry cleaner on your old PC you can get your B&W code back by doing this.
Click start then run type regedit. follow this path. HKEY_LOCAL_MACHINE\SOFTWARE\Electronic Arts\EA Games\Black and White\ergc this will reveal you lost key.
Wrire it down and exit without saveing. Job done.

That's unfortunate.  You really should keep a file of all your cd keys backed up on your computer somewhere.  We can't really help you short of what Gremxula said.