OFFSET FETCH in SQL Server 2008
Use a Common Table Expression (CTE):

    CREATE PROCEDURE [dbo].[sp_JobSearch]

    @EnteredKeyword nvarchar(200) = '', 
    @EnteredLocation nvarchar(200) = '',
    @PageNumber INT = 1,
    @PageSize   INT = 40

    AS
    BEGIN

    WITH CTE AS
    (
      SELECT 
        ROW_NUMBER() OVER ( ORDER BY [MasterJobId] ) AS RowNum ,
        MasterJob.Title, MasterJob.CompanyName, MasterJob.ShortDesc,      
        MasterJob.Url,MasterJob.PostedTime, MasterJob.Location, JobBoard.JobBoardName  
      FROM MasterJob 
        LEFT JOIN JobBoard ON MasterJob.JobBoardId = JobBoard.JobBoardId
      WHERE 
      (MasterJob.Title LIKE '%' + @EnteredKeyword + '%')
      AND( MasterJob.Location LIKE '%' + @EnteredLocation + '%' )
    )
    SELECT 
      Title, CompanyName, ShortDesc, Url, PostedTime, Location, JobBoardName
    FROM CTE 
    WHERE 
      (RowNum &gt; @PageSize * (@PageNumber - 1) )
      AND 
      (RowNum &lt;= @PageSize * @PageNumber )
    Order By RowNum 

    END