If your file is not too big to fit in memory, then 

perl -ne 'push@{$ndx{uc substr($_,0,1)}},$_;END{for(sort keys%ndx){pri
+nt":$_:\n",@{$ndx{$_}}}}' sorted.txt

[download]

In reply to Re: Find by Anonymous Monk
in thread Creating a text index for a text file by texuser74

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