Preaching the Lectionary: Reginald Fuller's work on lectionary preaching is one of the best one-volumes available. Ecumenical, smart, and a quick one-page-per-Sunday read.
General Preaching Links and helpful resources:
Catholic Coalition on Preaching
Dominican HS Preaching Resources on the Internet
St. Paul Center for Biblical Theology
Crossroads Initiative Catholic Bible Study
Phat Catholic Apologetics
Catholic Pages Directory