I drink lots of h2o and grn tea and have a low fat diet. I am not taking any vit. Suppls. There are conflicting opinions on supps. Should I take any?

Possibly. Taking vitamins (specifically multivitamins) is like having car insurance; you hope you never need it, but it's nice to have around when you do need it. The average american diet generally has sufficient vitamins and minerals for our body. More so if you eat a variety of items. However, illnesses, fad diets, lack of variety, and skipping meals increases your need for vitamin supplements.
To Supplement or Not. It depends on what type of supplements you're interested in using and for what purpose. A well rounded vitamin off the shelf is unlikely to be harmful and may help to provide a more complete intake if your diet is limited. Supplements often have specific indications and are typically compounded dry herbals, Amino Acids or liquid extracts from animals or plants, e.g. Fish oil or glucosamine, etc.