Thanks, everyone. I have been spending time on the bettafish.com forums, so I am getting Betta info there. There are mixed opinions about filters. My tank came as a kit so it does have a small filter, so I can see how well that works. Right now I don't need a heater because my apartment is ways hot and I rarely turn on the A/C. But I'm planning on getting one for the winter.
It came with a light hood and a 15 watt bulb, too.
Anyway, thanks for the tips and the links for more plant info.