Required Information and Documentation
To do any maintenance, the FARs require that you have the manufacturer's current maintenance instructions. These would include the airframe maintenance manual, the illustrated parts catalog, and other service publications such as service bulletins, service letters, etc. However the airframe manufacturer didn't make all the parts that are on the plane. The engine manufacturer has their own set of manuals, as do many accessory manufacturers. Having the manual for the magneto or the brakes and wheels is just as important when working on those accessories as is having the engine or airframe manuals.
That is a lot of manuals to locate, but fortunately, some suppliers are now offering their manuals on CD or even on the Internet. One such forward thinking company is Parker-Hannifin, the makers of Cleveland Wheels and Brakes. They offer manuals in print, on CD, and on the web for their Parts Catalog (16MB PDF) and their Maintenance Manual (16MB PDF). Note that the Cleveland manuals above are as retrieved in October 2009. It would be prudent to check with Cleveland for updates before considering these to be "Current Maintenance Instructions" as called out in FAR 43.13.
Unfortunately, Lycoming only has a small selection of their documents on-line. They can be viewed here.
Logbooks and Recording
The minimum requirements for logging work done on an aircraft or accessory is detailed in FAR 43.9. A log entry must include a brief description of the work performed, the date the work was completed, the name of the person that performed the work -- if different than the one making the log entry, the name, certificate number and type of the person making the entry and of course the signature, which the FAA says constitutes the approval for return to service.
The description of the work "should be in sufficient detail to permit a person unfamiliar with the work to understand what was done, and the methods and procedures used in doing it". A reference to standard methods, procedures and technical data may be made to keep from making each record too long if extensive work is performed.
The FAA has a detailed Advisory Circular on maintaining records - AC 43-9C.
Although we all think in terms of those little books that say "Aircraft Log Book" on the cover, the FAA does not actually require that we keep the records of the maintenance in a "log book". They can be a stack of loose sheets in a file folder, or even an electronic record -- like many of the airlines and the military use to track their maintenance. Caution is needed here though, per AC 43-9C, electronics records still have to meet the FAR requirements, including signatures, so a hard copy with a signature still seems to be needed.
With light planes its just easier to use the traditional log book, so that is how most owners of light planes manage their records. For our Grummans, time in service and details of the propeller, engine and airframe all need to be logged, while they could be in one logbook (again, per the AC 43-9C), as a practical matter, it's easier to have three separate log books.
The FAA wants a log book for each "Class 1 Appliance". Class 1 Appliances are those components that have a Type Certificate, such as the Airframe, the Engine, and the Prop(s) or rotor system. In the past it was common to include the prop in the Airframe logs, but more recent thinking in Washington suggests we have a separate prop log. So if someone hasn't already purchased a prop log and begun tracking the prop separately, now would be a good time to obtain one and add it to your maintenance records at the next inspection.