simonwilliams,

1.    if ($#bids){...}
   does what you mean, but it doesn't really say what you mean. For that, you should say
      if (@bids > 1){ ... };
   i.e., if @bids contains more bids than one, then ...
2.   for (my $i=1; $i<scalar(@bids); $i++) { ... }
   could be written ...
     for (my $i=1; $i < @bids; $i++) { ... }
   ... without any change in meaning. @bids is being evaluated in a scalar context. No need to say scalar() explicitly.
3. Let me oversimplify your problem, and you can build on that. You want to choose the highest bid, excluding your own from consideration (always the first bid), and print only the highest bid.

   my $highest;
   if (@bids > 1){
       for (my $i = 1; $i < @bids; $i++) {
           my ($alias, 
               $email, 
               $bid, 
               $time, 
               $add1, 
               $add2, 
               $add3, 
               $oqty, 
               $soldqty) = read_bid($bids[$i]);
           $highest = $bid > $highest ? $bid : $highest;
       }
       print "Highest bid: $highest\n";
   }
   [download]