Can tourists visa convert in to family visa or dependents visa?

It can be converted if:

The application is filed with at least 6 working days remaining in their tourist visa
At that time, the residence permit has been stamped in your passport and you have a CPR
You have all the marriage & birth certificates for the dependents (attested by MOFA in home country as well as Bahrain embassy - sometimes they make a fuss about this)

I would just like to clarify. If I am coming to work in Bahrain on a 2yt contract, and employer will not sponsor the family. Can I apply for wife a family, dependent or some other visa for her to be with my all 2 yrs?

You cannot apply for a dependent visa if your sponsor/employer does not agree.  While the dependent is under you in the system, the application is filed by your sponsor.

You can bring them over on visit visas but they will not be residents and will have to leave / re-enter on visit visa expiry.   Then you apply for another visa and then bring them in again.   Or do regular visa runs by entering and exiting if you have a passport that allows for visa free travel - but they can refuse you entry if they suspect you are doing it to live here.  Unlikely as lots of people do it but there is always a risk.

Try to talk to your employer to allow for sponsoring your family.  Offer to pay all costs for the visa.