One resource that I am reading through is Andy Stanley’s Communicating for a Change.  This quick narrative read clearly gives insight to simple steps to help in sermon/lesson preparation and delivery.

A critical issue here is, do you really think about your message?  I know that sounds simple, but do you think about your message/lesson and how it is coming across?  Is it understandable?  Applicable?  While not the only book on speaking, and not the only way of speaking/preaching, a read like this at least helps me pull out of some deep groves I may be stuck in.