• You can do this to get the plan:

    SELECT

    DEQP.query_plan

    FROM

    sys.dm_exec_query_stats AS DEQS

    CROSS APPLY sys.dm_exec_query_plan(DEQS.plan_handle) AS DEQP

    WHERE

    [some criteria to determine what is long running]

    Then you can examine the execution plan to determine where/what to start stuning.