Help me make a good Vanilla Latte

Hi,

I have a Super Auto Espresso Machine, Starbucks Espresso Beans, Vanilla Syrup from Starbucks, and nonfat milk (my milk of choice in these drinks).

I can't get the taste exactly right. In a Tall Vanilla Latte Non-fat, there is only 1 shot of espresso? How big is a Starbucks shot? Only 1 ounce or more? How many pumps of vanilla should I do? 3?

I think it's the espresso I'm not getting the correct amount. I don't know how many shots, or if they need to be bigger shots. My drinks are coming out a bit too milky I think.

Finally, why do the Starbucks employees get so mad when I try to order the bottles of syrup sometimes? The other day one refused to sell me any until "sometime later in the hour," so I left. No explanation despite my asking. She was very rude. I went to another store, and the guy smiled and got the bottle and pump (I had never gotten a pump before). I was very happy.

Thanks for your help!