It was a total surprise to me! I had no idea the 501st would be there, but VERY worth the nearly 3.5 hour drive! I had to share Everyone involved was great, and kudos to the bookstore employees who kept everything running smooth.
Link to the dates for the book tour? I think Karen's tour in the U.S. is over, but check out her website. That's how I found out about KT's signing--just ran across it on the web. Go to 501st.com as well--that might give you some info about appearances, too.
I'd say keep an eye on author's websites (if they have them) to check out book tour dates. For signings like this, I'd venture to say the 501st would likely have appearances along with them
Besides "Jango", I got to talk to a few other members of the 501st--I'm a new fan! Those guys are great
"Train your sons to be strong, but your daughters to be stronger."--Karen Traviss, Bloodlines