This pattern is for a plain necktie, with no pattern, so if you want a solid color tie, it's perfect.
If you want a multicolor tie, you could try using self striping yarn.
http://www.knitty.com/ISSUEspring03/PATTprepschool.html
I found this pattern also, but it's a makeshift clip-on tie, instead of an actual "tie around the neck" tie. Also, you'd have to enlarge it, as this pattern is for a toddler.
http://bluealtoknits.livejournal.com/19691.html#cutid1
These are the only two I've been able to find. Hope one of them can work for you. =)