Test Environment: MS Server 2008

For example to search all columns of all tables in Pubs database for the keyword “Computer”

CREATE PROC SearchAllTables
(
 @SearchStr nvarchar(100)
)
AS
BEGIN

 CREATE TABLE #Results (ColumnName nvarchar(370), ColumnValue nvarchar(3630))

 SET NOCOUNT ON

 DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110)
 SET  @TableName = ''
 SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''')

 WHILE @TableName IS NOT NULL
 BEGIN
 SET @ColumnName = ''
 SET @TableName =
 (
 SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
 FROM 	INFORMATION_SCHEMA.TABLES
 WHERE 		TABLE_TYPE = 'BASE TABLE'
 AND	QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) > @TableName
 AND	OBJECTPROPERTY(
 OBJECT_ID(
 QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME)
 ), 'IsMSShipped'
        ) = 0
 )

 WHILE (@TableName IS NOT NULL) AND (@ColumnName IS NOT NULL)
 BEGIN
 SET @ColumnName =
 (
 SELECT MIN(QUOTENAME(COLUMN_NAME))
 FROM 	INFORMATION_SCHEMA.COLUMNS
 WHERE 		TABLE_SCHEMA	= PARSENAME(@TableName, 2)
 AND	TABLE_NAME	= PARSENAME(@TableName, 1)
 AND	DATA_TYPE IN ('char', 'varchar', 'nchar', 'nvarchar')
 AND	QUOTENAME(COLUMN_NAME) > @ColumnName
 )

 IF @ColumnName IS NOT NULL
 BEGIN
 INSERT INTO #Results
 EXEC
 (
 'SELECT ''' + @TableName + '.' + @ColumnName + ''', LEFT(' + @ColumnName + ', 3630)
 FROM ' + @TableName + ' (NOLOCK) ' +
 ' WHERE ' + @ColumnName + ' LIKE ' + @SearchStr2
 )
 END
 END
 END

 SELECT ColumnName, ColumnValue FROM #Results
END

EXEC SearchAllTables 'Computer'
GO