I would do it like how Remi suggested. Just use the collate function and have the right capitalization in the Where clause:

To find lower case f:

select titledesc from tblproducts (nolock) where titledesc like '%f%' COLLATE SQL_Latin1_General_CP1_CS_AS

To find upper case f:

select titledesc from tblproducts (nolock) where titledesc like '%F%' COLLATE SQL_Latin1_General_CP1_CS_AS

Here's a resource you will want to check out: http://vyaskn.tripod.com/case_sensitive_search_in_sql_server.htm