Extract Unique Items w Formula For Data Validation Drop-Down List time 2

[machcc]

Extract Unique Items w Formula For Data Validation Drop-Down List, having two drop validations list unique values the second on dependant on the first. The link below is Excel is fun video that was a great experience. Basically I have two of this same type of situations and have completed making the two different drop down validations, but my second drop down is not dependant upon the first drop down. Please help

http://www.youtube.com/watch?v=IhuURsu0jdI