as long as you don't stress the clones too much they should stay female. For two plants I would recommend Compact Flourescent Lights, as they put out more light for the room they take up and are not very expensive. Get "Cool White" or "Daylight" color temperature ~6400k for vegetative growth and "Warm White" ~2700k for flowering.

You can leave the lights on 24 hours a day in vegetative growth and your plants will grow faster and do not need darkness.

Here's a decent Grow Guide to get you started.

http://www.nirvana-shop.com/info_growing_guide.php

and another

http://www.marijuanahydro.com/cannabisplant.html

Do not over water or over feed your plants. And read as much as you can. This forum has a lot of good stuff on it, use the search feature to find it.