Here we go again. Just as you’re finally choosing which netbook you’re going to buy on which carrier, here comes AT&T to make your decision even tougher. Or maybe, it actually makes things easier. As the world warms to 3G-equipped netbooks sold directly through mobile carriers, AT&T is doing its best to take advantage of the situation. And frankly, to take advantage of the uninformed.Let’s take a look at the mobile operator’s newest offerings. If you’ll recall, it started offering netbooks for sale at