Data validation list decreases as the user chooses from the list/s

[Emdyey]

I am trying to create a validation list in Excel 2003 with two or more
sub-lists. For example, the first validatation list contains 4 options. Each
option has sub-options. And each sub-option has sub-options also. I would
like to accomplish a list that when the user select 1 option from the main
list it will only show its sub-options. And as you select the sub-option it
will show the sub-sub-options.
Find below the illustration

List:
Actions => 4 sublists => each sublist => 10 sublists
Conditions => 4 sublists =>each sublist => 10 sublists
Personal Factors => 5 sublists =>each sublist => 10 sublists
Job Factors => 9 sublists =>each sublist => 10 sublists

Example:

Actions
l---> Following procedures
l----> Individual, Group, Supervision, Improper loading, etc.

l---> Use of Tools or Equipment
l---> Use of Tools, Use of Equipment, Use of Defective
Tools, etc.

And so on, so forth.

Hope you can help me with my problem.

Thanks in advance.

 

[Dave Peterson]

I'd start at Debra Dalgleish's site:
http://contextures.com/xlDataVal02.html