Here's part 2 of Lawrence Garvin's video series on 3rd Party Updates. This part covers package creation:
https://www.eminentware.com/cs2008/media/p/446.aspx
If you haven't seen part 1 (which covers setting up for 3rd Party Updates), you can view it here:
https://www.eminentware.com/cs2008/media/p/405.aspx
John
Here's part 3 - covers package creation in more detail:
http://www.eminentware.com/cs2008/media/p/503.aspx
Thanks Lawrence!