Water when the soil feels dry. This is not multiple times a day; rather, a few times per week, depending upon your soil.
The bulb that will fit in a regular socket is a CFL. It is a swirly flourescent energy saver light that is nice for growing plants too.
Keep your seedlings on constant light- 24 hours a day- until they reach sexual maturity at about 3-6 weeks old.
REad the link in my signature. It will tell you everyting you need to do a basic soil grow.