Nickr:
Neo offers good advice Get the lay of the land, don't worry about paying double (you mentioned tax dollars already paid, but Bowen Ranch is private land with access to BLM land). The Bowen trail is a great way to learn about the area, it has the easiest trails and great campsites. The sites are rustic, but you're used to that.
You mentioned you've been there before, but a reminder that you will most likely encounter nudity at any of the parking areas, the Bowen Ranch camping area and Deep Creek itself.

Have a good time - and just make it easy on yourself the first time out with newbies. Don't forget to bring a small trash bag, but if you do - there are always some available at the Bowen entrance.