Here′s the place to start if you are unfamiliar with drogues and sea anchors and their uses. Clear prose, but no pictures, and the original article is not available offline.
[Ocean Navigator, January 1995]
Lots of detailed advice on choosing, rigging, and using a sea anchor. A reference manual. Has links to instruction manuals for their product′s instruction manual.
[Para-Tech Engineering Co., Silt, CO, USA]
A 60-foot sloop loses her rudder at sea and the crew manages to sail her to port using a storm sail and drogue. The lessons learned include the best speed, and the right size, shape, and attachment point for the drogue,
[Cruising World, 5 July 2005]
Although written for powerboaters, a good source of information on drogue, sea anchors, and their deployment. Vendor list. 9 pages
[PassageMaker, April 1999]
If the rudder is lost, here is why steering with a jury rudder or drogue will require much greater forces than the two-fingers-on-the-wheel we are used to.
[Cruising World, 5 July 2005]
These cruisers deploys a Paratech sea anchor in gale force winds a few miles from shore, learning five lessons in the process.
[Fantasia 35 Owners, USA]
A very detailed computer and test-tank study of the interaction of boat, wave, and drogue. Lots of engineering, but also some detailed design information to use if you are thinking of carrying and rigging a sea anchor.
[U.S. Coast Guard, USA]
Tips for preparing for and handling heavy weather, including what storm gear to deploy such as sea anchors and storm canvas, with accounts of some storms managed under sail. 3 pages with list of sea anchor vendors.
[Ocean Navigator, July 2003]
FAQ entry about where to get the pattern to make a sea anchor yourself and when to use it.
[Cruiser Log, USA]
A drogue "may be even more critical to raft stability than ballast," and has other purposes according to this report, which looks at various (primarily aircraft) liferafts and how they rig a sea anchor.
[Equipped To Survive Foundation, Inc., USA]