What kind of conflicting advice did you have? You can plant the tank at any point in the cycling process. In fact if you plant it heavily prior to cycling it, you may experience a 'silent' cycle, which is basically the plants sucking up the nitrogenous waste before it gets to a detectable level on your test kit.
Fish-in Cycling: Step over into the dark side - Aquarium Advice
For substrate, I suggest a fired-clay type substrate. They do great at making nutrients available for plant roots. I don't know what they have available where you are, but substrate choices like ecocomplete, floramax, schultz aquatic plant soil, oil-dri, turf ace, or flourite are all good options. You could always just use plain sand as well, the plants will grow in it, but I don't believe that it does as good of a job as the type of stuff I mentioned previous.
