The first step in the process is to parse the the CSV. This is best done with a module such as Text::xSV.

Then, you need to figure out how to differentiate titles from other fields. It isn't apparent from your post, so I cannot help you there.

Finally, populate the hash. A most simple-minded solution would be to create a case structure:

my @titles = ...; 
if (@titles == 1) {
   $BIGLIST{$title[0]} = [ @RESTOFFIELDS ];
}
elsif (@titles == 2) {
   $BIGLIST{$title[0]}{$titles[1]} = [ @RESTOFFIELDS ];
}
...etc.
[download]

This works is you have some small upper bound of titles. If not, you will need a loop that walks the @title array (untested):

my @titles = ...; 
my $ref = \%BIGLIST;
while (@titles > 1) {
   my $title = shift @titles;
   $ref = \($ref->{$title});
}
$ref->{$title[0]} =  [ @RESTOFFIELDS ];
[download]