No it's not you at all. I have made a patch for ExtUtils::Installed that will allow you to supply a list of locations which are outside the perl install prefix - I need to add some tests and change the documentation before I send it to p5p but this:

--- Installed.pm.orig   2004-07-20 16:37:50.000000000 +0100
+++ Installed.pm        2004-07-20 17:23:53.000000000 +0100
@@ -77,24 +77,32 @@
 }
  
 sub new {
-    my ($class) = @_;
+    my ($class, @dirs) = @_;
     $class = ref($class) || $class;
     my $self = {};
  
-    my $archlib = $Config{archlibexp};
-    my $sitearch = $Config{sitearchexp};
+    push @dirs, $Config{sitearchexp}, $Config{archlibexp};
  
     # File::Find does not know how to deal with VMS filepaths.
-    if( $Is_VMS ) {
-        $archlib  = VMS::Filespec::unixify($archlib);
-        $sitearch = VMS::Filespec::unixify($sitearch);
-    }
  
-    if ($DOSISH) {
-        $archlib =~ s|\\|/|g;
-        $sitearch =~ s|\\|/|g;
+    foreach ( @dirs ) {
+       if (!m!$Config{archname}/?$!) {
+              $_ = File::Spec->catfile($_, $Config{archname});
+       }
+
+       if( $Is_VMS ) {
+           $_  = VMS::Filespec::unixify($_);
+       }
+
+       if ($DOSISH) {
+           s|\\|/|g;
+       }
+
     }
  
+    my $archlib = @dirs[-1];
+
+
     # Read the core packlist
     $self->{Perl}{packlist} =
       ExtUtils::Packlist->new( File::Spec->catfile($archlib, '.packli
+st') );
@@ -108,11 +116,15 @@
         # Hack of the leading bits of the paths & convert to a module
+ name
         my $module = $File::Find::name;
  
-        $module =~ s!\Q$archlib\E/?auto/(.*)/.packlist!$1!s  or
-        $module =~ s!\Q$sitearch\E/?auto/(.*)/.packlist!$1!s;
+
+        foreach my $dir ( @dirs ) {
+           $module =~ s!\Q$dir\E/?auto/(.*)/.packlist!$1!s and last;
+        }
+
         my $modfile = "$module.pm";
         $module =~ s!/!::!g;
  
+       print $module,"\n";
         # Find the top-level module file in @INC
         $self->{$module}{version} = '';
         foreach my $dir (@INC) {
@@ -131,8 +143,8 @@
           ExtUtils::Packlist->new($File::Find::name);
     };
  
-    my(@dirs) = grep { -e } ($archlib, $sitearch);
-    find($sub, @dirs) if @dirs;
+    my(@search_dirs) = grep { -e } (@dirs);
+    find($sub, @search_dirs) if @search_dirs;
  
     return(bless($self, $class));
 }
[download]

use ExtUtils::Installed;
                                                                      
+          
                                                                      
+          
use lib qw( /home/jonathan/foo/lib/perl5/site_perl/5.8.1);
                                                                      
+          
my $ff = ExtUtils::Installed->new('/home/jonathan/foo/lib/perl5/site_p
+erl/5.8.1');
                                                                      
+          
print $ff->files('Foo','all');
[download]

/J\

Lovely, thanks!

Can I change

- push @dirs, $Config{sitearchexp}, $Config{archlibexp};
+ unshift @dirs, $Config{sitearchexp}, $Config{archlibexp};
[download]

because $sub (in ExtUtils::Installed->new)loops through the @dir array and sets $self->{module}{packlist} so if we push them on then if a module is installed in the dir you specified and in say /usr/local, we will always get back the packlist for /usr/local - which isn't very helpful if you want to uninstall something in a local directory. If you want the /usr/local version, just don't give a local dir in the call to new.
If that change is OK, then I wrote a quick thing for easy command line uninstall. Spot any glaring errors?

#!/usr/bin/perl 

###############################################################
# Uninstallation of perl modules 
################################################################
use strict;
use warnings;

# Need a patched version of ExtUtils::Installed to allow you
# to uninstall from locations other than the standard perl libs
use lib '/home/bsm/johnston/casspm/lib/perl5';  

use Config;
use ExtUtils::Installed;
use Cwd;
use Data::Dumper;

my @locallibs;

#########################
#get @locallibs - create a ~/.myperllibs file if necessary
#########################
my $cwd = getcwd;
chdir();

unless (-e ".myperllibs")
{
   #get any libraries the user wants to add
   print "\n#####\nI can't find a list of your user perl libraries\n".
         "I will create one for you now.\nTo add libraries to it in th
+e future, just add them to the file .myperllibs in your home director
+y.\nOne directory path per line.\nStandard installation libraries lik
+e /usr/local/lib or /usr/lib will be used anyway - you don't need to 
+add them to your file.\n#####\n\n".
     "Would you like to add any libraries now?[y|n]\n";

   if (<>=~/y|Y/)
   {
       print "\nEnter your library paths, seperated by spaces\n:";
       @locallibs = split(/\s/, <>);
   }
   
   #create a new file
   open LIBFILE, '>.myperllibs' or die "\n####\nSorry, I don't seem to
+ be able to make a ~/.myperllibs file.\nTry creating a file called:\n
+\t'.myperllibs'\nin your home directory.\n####\n\n"; 

   #write libraries (if any) to the file      
   foreach (@locallibs){
       print LIBFILE "$_\n";
   }
   close LIBFILE;

print "\nCreated library list in your home directory (.myperllibs)\n\n
+";

if (@locallibs){
    print "Added libraries:\n";
    map {print "$_\n"} @locallibs; 
    print "\n";
}
      
}

open LIBFILE, '<.myperllibs' or die "Can't open library file, but it e
+xists.\nGuess it might be a permissions problem?\n";
@locallibs = <LIBFILE> unless @locallibs; 
close LIBFILE;
chomp @locallibs;

chdir($cwd);

#####################################################
# what are we uninstalling and where from?
#####################################################
print "Which modules would you like to uninstall?\n".
      "Enter their names, seperated by spaces\n";
my @mods = split(/\s/,<>);

print "\nDo you want to look in the default libraries:\n".
      "\t$Config{archlibexp} and \n".
      "\t$Config{sitearchexp} ?\n".
      "('n' will use only libs in your .myperllibs file)\n".
      "[y|n]\n";

my $justmylibs = (<>=~/y|Y/) ?  0 : 1 ;

print "Uninstalling modules:\n";
foreach (@mods)
{
    print "\t$_\n";
}
print "Looking in directories:\n";
unless ($justmylibs)
{
    print "\t$Config{archlibexp}\n\t$Config{sitearchexp}\n";
}
foreach (@locallibs)
{
    print "\t$_\n";
}
print "\nOK to continue?\n't' will do a test uninstall (doesn't remove
+ any files)\n [y|n|t]\n";
my $ans = <>;
die "bye" unless ($ans=~/y|Y|t|T/);
my $testing = $ans =~/t|T/ ? 1 : 0;



####################################################
# Do the uninstallation
####################################################
foreach (@mods)
{
    my $inst = ExtUtils::Installed->new(@locallibs);
    my $found = $justmylibs ? 0 : 1;

   foreach my $item (sort($inst->files($_))) 
   {   
             if ($justmylibs)
         {   
             
         #ignore everything in default libs
         if( map {$item=~/$_/} @locallibs){
             $found = 1; 
         }
         else{
             next;
         }
         }
             print "removing $item\n";
             unlink $item unless $testing;
   }

   unless ($found) { 
       print "\n$_ doesn't seem to be installed in:\n";
       print "\t$_\n" foreach (@locallibs);
       print "If you're sure it's there try deleting the files by hand
+.\nSorry I can't be more help...\n";
       next;
   }

    my $packfile = $inst->packlist($_)->packlist_file();
    print "removing $packfile\n";
    unlink $packfile unless $testing;
       
}
[download]

You have to watch the order the things go on the @dirs because it does my $archlib = @dirs[-1]; after the paths have been munged. I only did that for convenience and not special case it at that point.

But the script looks like it should work fine.

/J\