I'll just add mine is on the back of the manual. I bought the one with "bonus material included" on the big case. Not that it matters, you mentioned you lost or threw that stuff away. This is the precise reason I'm a packrat at the expense of a cluttered house. I used to save old nuts and bolts and screws, brackets, cables, computer stuff ect.. Eventually I throw it away and what happens then? A week later I need something I just threw away....
Good luck with ubisoft. Personally I wouldn't waste my time, I hate the fact that I've bought numerous games on Steam that I already have on old cd's, but it's just not worth the hassle and I pony up the cash rather than deal with the aggravation.