In Malaysia, there is no office of Employment/Labour Law.
However, the Ministry of Human Resources is responsible for coordinating and managing the formulation, review and amendments of all laws and gazettes under the Ministry's purview (Employment/Labor).
There is also the Department Of Labour Peninsular Malaysia(west Malaysia) being responsible for providing services e.g. labor court, employees complaint, etc. to ensure an employee is protected under the Employment Law and enjoys the benefits under the law in addition to preserving the interest of an employer.
The contacts are as follow :
DEPARTMENT OF LABOR PENINSULAR MALAYSIA,
Paras 5, Blok B Utara, Pusat Bandar Damansara 50532 Kuala Lumpur
TEL: 03-2557200 FAX: 03-2536040
MINISTRY OF HUMAN RESOURCES,MALAYSIA
Level 2-4, Block B (North), Jalan Damanlela, Pusat Bandar Damansara, 50530, Kuala Lumpur.
TEL: 03-2557200 FAX: 03-2554700
As far as I know, you do not need to send a copy of the letter to the department. (if you do, enclose a covering letter would be better, as I have doubt whether they will keep a copy of your email).
As long as you have the copy of the resignation letter, employment contract, last payment slip, NRIC and address and company contact, you can file in any complaint to the Department of Labor Peninsular Malaysia by providing such proof and/or other information.
P.S. I believe your posting should be posted in the Labor Law forum. Its a moderated forum.