Over the last few months B & B members have ventured into the world of fountain pens as well. The question that always comes up is, what about the ink. Here is a link to a great web page that has all the info you need about ink.
Glenn Marcus on Ink
Unfortunately there is no mention of the excellent Pilot Iroshizuku ink which is a beauty ink in a beautiful bottle. This from the Mels Pens web site:
Pilot Iroshizuku ink is a luxurious ink collection. The ink colors reflect the beautiful natural scenery of Japan. The gorgeous shades fills the fountain pen with bold, beautiful and vivid colors, available in 16 different unique colors. Each bottle is a beautifully crafted glass container designed with an innovative dip at the bottom to ensure the savory enjoyment of every last drop. The ink bottle contains of 50ml ink.
If you are in a major city there should be a shop that sells most of these inks. On the web there are any number of sites that sell all of these inks. Can't say if one is any better than the other.