You might want to consider a half-way house which is to buy solid ink sticks (sometimes called Chinese ink sticks). To these you would just add water when needed, and perhaps Arabic gum to alter the texture a bit.
If you're still determined to make your own:
Try to track down this guy, Philip Steer , who has experimented with lots of calligraphy ink recipes already. He concluded that Edward Cocker's recipe performed best, but I haven't found a copy of that on the Internet.
Browse the archives of Cyberscribes on Yahoo; if no recipes there then send a message to the group asking for one.
For generic inks, not specific to calligraphy:
Some modern basic recipes, and cooking tips.
Old writing and drawing ink recipes.
Custom colourful inks, from mixing existing inks together.