Outside temperature sensor is located behind the front bumper in front of the left front wheel. The same sensor fits almost all BMW models since 2003. BMW part number is: 65 81 6 936 953
See figure 1 in attached image.
Retail list price is $88, club price is $65 new, but I'm willing to pay as much as 30 bucks for a used unit since I'm putting it on a used car.
So if you have one of these little gems sitting on a box somewhere or if you know someone who's stripping a car down for racing for instance, please PM me. Thank you.