antigua 007 has already received the plans.

As an additional explaination:
I shape my hullplugs out of solid foam and cover them with three to four layers of 160 gr. glass (twill) with epoxy resin.
Then they are sanded (grain 40, 80, 120). PVA mold release is applied.
Then I laminate the lightweight shells with two layers of 160 gr. glass and two layers of 80 gr. glass.
Each single shell is sanded with the same sanding grains (40,80,120),
before I remove it from the plug.
This can be done with two layers of 160 gr. carbon also.

It is also possible, to cut out the cross sections from 3mm balsa and plank them up with 3mm balsa planks as well.
Then the hulls are covered with two layers of 160 gr. glass.

To make the building process easier for everyone, there are several picture galleries of different modeltrimarans at:

http://community.webshots.com/user/boatbuilder

http://www.rc-network.de/forum/showthread.php?t=45060

http://www.rc-network.de/forum/showthread.php?t=94097