You will need T5HO lighting as well as good substrate if you are serious about having a planted aquarium. You can see my planted aquarium in my signature with all equipments listed except for CO2.
I am still testing around with CO2, and current CO2 is just DIY.
If you have never used CO2 before, it is a good idea to try out something cheap first before throw a lot of cash on a standard system that can cost a fortune. Try something cheap like Fluval Pressurized CO2 Kit.
In my experience, CO2 does make my plants grow faster. The biggest problem with a heavily planted tank is algae covering and killing plants. The only true way to keep the tank looking excellent is to keep trim away and replant the top very often. CO2 can help plants outgrow algae.
