Implemented in SQL Server:
This function finds a text string in a stored procedure or function definition:

CREATE FUNCTION Find_Text_In_SP_or_FN (@StringToSearch varchar(100))
RETURNS @fNames TABLE (name sysname)
AS
BEGIN
   SET @StringToSearch = '%' + @StringToSearch +'%'
   INSERT @fNames
   SELECT DISTINCT SO.Name
   FROM sysobjects SO (NOLOCK)
   INNER JOIN syscomments SC (NOLOCK) on SO.ID = SC.ID
   AND (SO.Type = 'P' OR SO.Type LIKE '%F%')
   AND SC.Text LIKE @stringtosearch
   ORDER BY SO.Name
   RETURN
END
GO

This function finds a text string in a column name:

CREATE FUNCTION Find_Text_In_Column_Name (@StringToSearch varchar(100))
RETURNS @fColumnNames TABLE (colname sysname)
AS
BEGIN
   SET @StringToSEarch = '%' + @StringToSearch + '%'
   INSERT @fColumnNames
   SELECT DISTINCT SC.NAME
   FROM syscolumns SC (NOLOCK)
   WHERE SC.NAME LIKE @StringToSearch
   ORDER BY SC.Name
   RETURN
END
GO

Some example usage for the novices:

select * from Find_Text_In_SP_or_FN('addr')
GO
Select * from Find_Text_In_Column_Name('city')
GO
Select * from Find_Text_In_Column_Name('state')
GO