Get Datatabase LOG Size

SELECT
     (size * 8)/1024.0 AS size_in_mb,
     CASE
        WHEN CAST( max_size AS BIGINT )= -1 THEN 9999999   -- Unlimited growth, so handle this how you want
        ELSE (CAST( max_size AS BIGINT ) * 8)/1024.0
     END AS max_size_in_mb
FROM
     sys.database_files
WHERE
     data_space_id = 0   -- Log file