Some plants are self-pollinating; you'll have to do some research on your particular species. Otherwise, the fan should work. If you really want to make sure they pollinate, you can use a q-tip and dab the flower centers to other flower centers. However, the easiest method would just be to set the plant outside during daylight hours.

Are you keeping them inside or setting out as transplants?

Most people that I know pinch the blossoms back before transplanting, in the thought that the plant will grow stronger roots after transplanting. That way they will have better production through out the year, instead of ripening those first few blooms.

Also, if you aren't sure what kind you have; for most tomatoes, all you have to do is given them a little shake in late morning to pollinate them or if they are outside you can let the wind or bugs do it.

These are Jet Star Tomatoes. Very big and will put them out in the garden when frost danger passes. Most of my tomatoes will be the normal size for transplanting but I was hoping to hurry up some tomatoes by growing them inside and then putting them out later (just experimenting) I do have a fan on them at least 12 hrs daily.
Thanks everyone for the information

Which lighting fixture do you use? how is the par value?