Seems to work for me. I ran the following code, and I get the result of match. Is there anything else in your code?

#!/usr/bin/perl
use strict;
use warnings;

my $searchstring = 'Price: \$([0-9]+\.[0-9]+)';

$_ = 'This is a test. Price: $1.30';

if( /$searchstring/ ) {
  print "match\n";
}

__END__
match
[download]

By the way, you can also set up the regex using the qr operator, like:

my $searchString = qr/Price: \$([0-9]+\.[0-9]+)/;
[download]

Wish I could help more,
-v