At what point in your pregnancy did you take you child birth class, breast feeding class, etc? How did you decide which ones to take?

My hospital offers 'Preparing for Childbirth with a Midwife' (I see a midwife practice and they will deliver unless there is a problem). I'm due at the end of July, and DH has a huge exam the first weekend of June, so pretty much we are looking at trying to do any prep classes between that time. Right now the only one on the hospital's schedule is the weekend my sister was going to have my shower, 4 hours away, though we could change the shower to later (getting closer to my due date, though). They will likely add more classes to the schedule, but I'm not sure. Just sort of wondering when is too late for these things, or if you got to a certain point where you were freaking out by not feeling prepared, or if you felt you did it too early and forgot stuff...

Or, maybe I am over thinking, but as probably a lot of people on here to, I like to be prepared, even if I'm over-prepared!