About the only tea I've ever enjoyed was the tea served with the food at a chinese restaurant I used to frequent (I don't think it was a green, and it was very mild).
Congratulations on your revelation that soda may not be the best choice in consuming nowadays. The drinks on the market today are less natural than they were in the past with all of the artificial sweeteners and the sugar equivalents like high fructose corn syrup, and huge amounts of caffeine in energy drinks. I just hope that there are more people like you making a conscious decision to do something about it.
Now to get to your post, are you sure the tea you had at the chinese restaurant was green tea? Most chinese restaurants in my area serve oolong tea. I love oolong as much as green which is why I thought I'd mention it.
It sounds like you may have resolved your steeping issue. I agree with the person that suggested getting a thermometer. It sure beats boiling water, then guessing what the temp is after you boil it (or before) and then pouring the water on the precious green or white tea leaves hoping you didn't burn them. You can get them at Target for 10-15 dollars.
My next investment will probably be a digital scale. This forum has discussed scales in the past and the one I have my eye on is called a "My Weigh 300-Z". It's about 20 dollars online, but I still guesstimate roughly 3 grams per 6 fluid ounces. Or One table spoon for 6-8 fluid ounces. This varies among people and it's your preference, so the sky is the limit.
Also, you might try infusing the tea (steeping the tea) more than once. Loose leaf tea is usually good quality where you can infuse the tea (with a bit higher temps and for longer infusion times) and still not lose taste. It's a great way to drink lots of tea using the same leaves! Again, this is personal preference, but I've heard of people steeping tea for up to 5-6 times.
I'm still a beginner also, but love to learn about and enjoy tea.