clone 555-
www.plantgeek.net is a great place to go and research aquatic plants.
There are all different kinds of substrates(gravel, sand, flourite etc) out there to grow plants in. It all depends on how you want your tank to look, what your fish needs are and what your plant needs are.
I have plants growing in several size gravel, sand and eco-complete(special for plants), so just depends on what you want

Do some research, figure out what you want to do and then work towards that. If we can help in anyway please let us know.
Carol
Carol