First thing you will need following documents:
1) Application for each visitors separately typed in arabic. You get this application form from moi website or u can get typed from the people sitting outside immigration office with typewriter.
2) NOC from company stating your salary and if accommodation is provided by company ask company to mention it in your letter.
3) In case you are not getting accommodation thru company you need to submit housing agreement. (No baladiya attestation required for visit visa.)
4) Marriage certificate copy attested & for your child birth certificate copy attested.
5) Your Passport copy.
6) Your ID Copy. Proffesion should not be technician or helper category.
7) Your wife Passport copy.
8) Your child's Passport copy.

Make two different set for each visitors.

With this documents go early inthe morning at immigration office. Once you get the reciept after submission you will be asked to check website in the evening with the no. provided on ur receipt. When u see ur visa is approved u hv to go to immigration office pay the amount and get visa printed. Gud luck.