Here's a list of the seminars available FREE from the Sovereign Grace website from their WorshipGod08 conference.
Band on the Run (Bob Kauflin) is a brilliant seminar for all musicians (especially keyboard players) and anyone who leads or arranges music. You can watch the seminar and download the notes here. You can also get the same seminar from the 06 conference where the theme is the same but the content is totally different.
The Task of a Worship Leader (Bob Kauflin) - For Worship Leaders (duh!) Bob preaches through part of his excellent book. Classic stuff.
When Leading Worship Is Your Second Job (Matthew Williams). A great roundtable discussion with a group of non full-time leaders. Topics includes 'how much time should you spend preparing?', rotas, team size etc.
Leading Worship in a Small Church (Pat Sczebel)
Planning for Sundays (Jim Donohue and Joseph Stigora)
Building Bridges: Pastors and Worship Leaders (Bob Kauflin)
Pursuing and Enjoying Spontaneity in Worship (Craig Cabaniss and Pat Sczebel)
What the Psalms Teach Us about Songwriting (Mark Altrogge, Steve & Vikki Cook)
Vikki wrote 'Before the throne of God above' and Mark wrote 'You are beautiful beyond description' and many others. It's basically a ramble on the subject of songwriting, doesn't really stick to the topic of the Psalms but well worth a listen, especially if you've never heard these masters teach on songwriting before.
Writing Songs People Will Want to Sing (Craig Dunnagan)