Our K orientation is on Aug 15th and I think that's when we will find out teacher placement. It's on the schools website.
I think that teacher placement way ahead of time is hard because people register up until the last minute. At our school the kids are provisionally placed and then the first week or two they are assessed for academic skills and moved around as needed. For example, all the early readers are placed in one class so that they can have a reading group from the first few weeks.
Call the school and ask if there is a K orientation.

Bus info usually goes out just before the school year starts, as routes and stops are heavily dependent on final enrollment.

It's nerve wracking. I know. But, it WILL come. You can look on the pgcps.org website and see bell times for individual schools for the upcoming year. (Mine's going into middle school, and the bell time changed this year). Also, if there's a problem with it, the transportation department is pretty good about working with parents. We've gotten stops moved to better intersections before due to traffic concerns or number of kids. The bus situation always takes a few days to shake into a smooth rhythym at the begining of the year.

Regarding open house, it's usually AFTER school starts. That said, I think going with your kindergartener the very first day is A-OK.

Also have a child entering kinder and we've heard nothing.

When does the county typically send out information regarding bus transportation, teacher assignments, etc.

I am the parent of a child entering kindergarten and I am working in the dark here. School starts in 3 weeks and the only info I have is the school hours.

Do they not do an open house or a back to school night before the school year starts?