could be a little more specific than 'sound program', do u mean sequencer or audio editor.
For sequencing: on a tight budget go for Fruity Loops Studio, if you can push the boat to around £200, definetely get Reason - if you've got more money than sense go for Cubase SX and a load of VST plugins.
For audio editing: Cool-Edit (i think's it adobe audition, now), Sound Forge or Wavelab.