I don't think this is a boundary issue, nor would I feel guilty about Googling a T. I Googled my T when I first started seeing him. It made me feel more safe and connected. If T's are putting information online, I would assume they should feel comfortable having anybody, including clients, access it.

That said, too far for me would be looking up tax records, their home address, or trying to figure out where they will be and when to track them down outside of session.