Was this an OEM or retail box?
If yes, email creative, tell them there was no CD in the box, Best Buy treated you very poorly, and ask them to mail a CD or for a place to download an ISO you can burn. Or just return the damn thing and tell the manager your lucky you don't file business fraud charges against him. Then email Best Buy corporate with the story. Best Buy has been slammed for bad business practices by several states.
Was it a returned item on the junk table?
You're screwed, those usually sell "as is". Ask around for someone with one you can burn a copy of the CD from.