Google shareholders who have a few extra thank you notes sitting around might consider sending them to AT&T, the Apollo Group, and Expedia, along with a handful of other companies. New data identifies these organizations as the biggest AdWords spenders in June (and pins down the dollar amounts involved). Michael Learmonth apparently obtained "an internal Google document," and it showed that AT&T spent a whopping $8.08 million with Google in June alone. The Apollo Group,