Most probably your name would not have been shown in the attendance register or any statutory notice sent to the labor department authorities. How the salary is paid - through bank or in cash? This is certainly an unscrupulous act on the part of your employer to deprive your proof of employment under him. In this circumstances, you cannot get a pay slip from him. I think some more employees would have been facing the same problem. Better join together and lodge anonimous complaints to the authorities concerned fortwith . No other thing will be possible at this juncture to get a pay slip from such an employer.