Fellow Monks:
I need help 2 fold with regular expressions, for I realize they are exceptionally useful, but, unfortunately even the simplest aspects, as seen in my code snippet below, confound me.
First: What I would like to do is conduct a directory listing, (not a problem), and match into a directory via grep files that meet only the following criteria: match the front part of the filename, a fixed string, and the back part of a filename, essentially a fixed extention; where AAAAAnnnnn.txt; AAAAA is the front half of the filename that is fixed, to be matched; nnnnn is the part of the filename the changes and .txt is the fixed extension.
the code attempt (a snippet): 
my $datadir="/user1/localfiles/data/"
opendir LOCALDIR, "$datadir" or die "unable to open $datadir\a\n";
my @localfiles=grep/(^file-15a_62_200405)&&(.txt$)/i readdir LOCALDIR;
foreach my $file(@localfiles)
{
print "$file\n";
}

[download]
shown above is my blind (lack of knowledge) attempt which obvoiusly didn't work. Originally the grep line was just set to match just the extension, 
my @localfiles=grep/.txt$/i readdir LOCALDIR;

[download]
or I could match the beginning with: 
my @localfiles=grep/^file-15a_62_200405/i readdir LOCALDIR;

[download]
which worked just fine. In a nutshell.... I simple do not know how to combine the two. I would really appreciate your help in this matter and I humbly thank you in advance.
The Second Part:
My first thought was to look for tutorials on regular expressions, I googled and found a list longer than my arm. Are there any recommended tutorials for regular expressions favored among the community? I am looking for simplicity and practical application of regexes..... something to start me out from the very beginning.... again many thanks.

In reply to Simple Regular Expression Help Needed by PerlBear

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