Aldila
Manufacturer of graphite shafts for OEMs. Shaft specs online but no technical or manufacturing details. Materials section has information about Aldila prepregs and fibers.

Callaway Golf
Designs and manufactures golf clubs, many with composite shafts. Corporate and product information. Some technical details, but I couldn't find anything on the shafts.

Clubmaker Online
Meta-site with graphite shafts and other components from various manufacturers. Technical information covers club making.

Golf Engineering
Manufacturer of Silkwoods woods. Some interesting information on the technology and physics of golf.

Golf Guide
If you're interested in playing golf and not just reading about the materials used in the equipment, see About.com Guide Timothy Church's site.

HST
Manufactures carbon golf shafts for OEMs. Overview of facilities and processes, but not much technical detail.

Innovative Sports Technologies
Manufacturer of carbon golf shafts. Brief technical overview, including sheet rolling vs. filament winding, and a micrograph comparing high pressure cure to low pressure cure.

ShotSavers Golf
AJ Red Hot Shaft from AJTech. A gripless shaft made from graphite composite and metals. No technical information.

Sports News Archive
Archive of composite news items related to sports and sports equipment.

World Co. Ltd.
Division of Hankuk Fiber that manufactures Fiber-X carbon golf shafts. Descriptions of the shafts, but no technical details.