This letter would most likely accompany a brochure. If not, you must be specific as to benefits to the reader, cost, location and timing of the seminar. Encourage early registration by offering an early registration discount.
1234, Main Street
Boston, MA 02123
08 April, 2005
<Recipient Address Goes Here>
<Customer need.>. <Workshop or seminar description.>
This <duration> will give you everything you need to know about:
- <list of topics>
<Name> will be held <location, dates, and times>.
If you register by <deadline> the price will be <$price>. After <deadline> the price will be <$price>. We look forward to seeing you at <Name>.
encl: <List of enclosed items goes here>