How to find non-existing records?

I have 3 Tables

Table 1 is a Trainings Table:

TrainingID	Name	Someotherfield
1	aa	whatever is
2	bb	in this field

Table 2 is an employee list

EmpID	LastName	FirstName	DOB	etc.
1	John	Doe	mm
2	Jane	Foe	yy

Table 3 is the table where these two tables meet :

EmpID	TrainingID	Compdate	etc
1	3	ddmmyy	x
2	1	ddmmyy	x
2	2	ddmmyy	x
2	3	ddmmyy	x

What I need to be able to do, is query these three tables and return an EmpID and a TrainingID that are both not in the third table, so in this example my ideal response would be :

EmpID	TrainingID
1	1
1	2

What I have managed to do so far, is not great:

SELECT * 
FROM CompletedTrainings
LEFT JOIN Trainings ON Trainings.TrainingID = CompletedTrainings.Training
WHERE ISNULL ( Trainings.TrainingID

This returns a list of employees, but not the training numbers that are missing.

I have tried a variant of this using NOT EXISTS:

SELECT CompletedTrainings.Employee, CompletedTrainings.Training
FROM CompletedTrainings
WHERE NOT EXISTS (
SELECT TrainingID, [Training Name]
FROM Trainings
WHERE Trainings.TrainingID = CompletedTrainings.Training);

This again returns a list of employee names, but not the names of the missing trainings. How can I do this?

Solution

Use a cross join (via ,) in MS Access and then not exists or left join:

select t.*, e.*
from trainings as t,
     employees as e
where not exists (select 1
                  from employeeTrainings as et
                  where et.EmpID = e.EmpID and et.trainingID = t.trainingID
                 );