Everything you ever wanted to know, and then some:
Safe Anchoring
Also, I would recommend taking additional rope for a stern line. When we gunkholed the San Juans and Desolation Sound there were many bays that were tidally influenced. We would bow anchor in the bay and tie a stern rope anchor to land to keep us stationary in the deep water. Bring a raft to get to and from shore.
Have fun! There are lots of gunkholing books out that can really help you plan your trip.