What?
The Pilgrim Cell Tome of Hostilities is a multi size book that contains empty tracking templates with which to construct different force lists to game with. Tome of Hostilities Tracking Sheets are compatible with all RKE Skirmish Games.

Format
ToH comes in PDF format for free and may be downloaded HERE.

Tracking Sheets
The Tome of Hostilities lets you build a single force with 1 Cover Sheet, 8 Character Sheets, 1 Game Sheet, 1 Vehicle Sheet, 1 Play Sheet and 1 Force Note Sheet. So when I say you can build 10 or 20 or 40 force list that means each force list contains 12 tracking sheets plus a cover sheet with which to build a force.

Statistics - Click for Previews and Descriptions of Tracking Sheets
Statistically speaking all 12 tracking sheets which compose one force list in the Tome of Hostilities let you do the following:

1. Cover Sheet x1 - The Cover Sheet is included at the begining of a set of tracking sheets to help categorize your Force Lists. It contains blank areas for force name, what game and force number. Force number is written and cross referenced to the Tome of Hostilities Index so you know roughly where in the book the force presides.

2. Character Sheet x8 - Write down 16 totally different units with 4 statistically different models in each units with spaces for 6 different weapons and 6 different abilties. So you could have a unit with a leader, grunt, specialist and captain with all thier stats, weapons and abilities in just 1 of your 16 Character Sheet Slots.

3. Game Sheet x1 - You can track the full damage of 40 different models on the game table not including vehicles and thier crew. Also you can track 12 units for 18 Force Cycles ie which units have been activated in the current cycle.

4. Vehicle Sheet x1 - You can track up to 8 vehicles of varying sizes with a total of 14 crew members. So the vehicle sheet combined with the game sheet tracks 54 models and eight vehicles damage. If your force is bigger than that your SOL.

5. Play Sheet x1 - The Play Sheet tracks up to 8 hidden units and where they are secretly deployed on the table and if they are hidden on terrain with multiple levels. Also it tracks up to 9 units for a total of ten Force Cycles that are under various game effects like poison, slow, mutate, etc. The Play Sheet also contains an area for wirting down the names and point costs of 16 units and also what happened when you played with this force list ie win/loss, how long was the game etc.

6. Force Note Sheet x1 - This sheet lets you write down your various thoughts on how your composed force list worked out, what you would change, strengths/weaknesses etc. So if you fought a variety of other armies with yours you could write notes to recomend, "Switch this unit with a more effective unit when battling so and so."

Personally
What I would do is write down "test" force lists on blank sheets of paper and after testing the force and working various kinks out of it I would then put it into the Tome of Hostilities as a "battle tested" force list that I could use later.