Dear Nisha,
You have to approach Tahsildar office. like for Kurla Ghatkopar at Mulund Tahsilder Office at Mulund Court. They give you for which cost Rs. 30, stick Rs. 5/- revenue stamp. You need to fill in lot of details in it. They have divided the same in to two religion maharashtrains and non maharashtrains. Along with the Form you have to give caste certificate of the father or near relative of the person you are going to make the certicificate. LIke for instance if you getting for your child. the child father or near uncle should have the caste certificate from your village tahsilder etc. Along with the form there is an affidavit, address proof, date of bith proof, ration card and Bonafied certificate from school that is required.
Once you submit they send the father caste certificate for verficiaion if it is non maharashtrains. once they get the confirmation then they issue the certificate. It take months. if they dont then you it falls under verifiction you have to get the same done on their behalf. and see that it is submitted.
in liue of the application submitted they issue you a slip which you have to carry in exchange of your certificates.
I hope this information provided may be useful to you.
Advocate asgarali attarwala