RE: Cost effective to switch now?
It depends on how you diaper.
The aboslute most cost effective way to cloth diaper is with chinese prefolds (CPFs in the abbreviations). You can get 2 dozen diapers and 4 covers for $70-$80. That is a minimal, but probably sufficient amount of diapers. If you buy premium size, then that may be all you would need. But there is the possibility you might need to move to toddler size prefolds later. A set of those would be in the same $ neighborhood. Also plan to spend a few extra dollers for liners, a pail and some doublers. So $100 would certainly get you going and would be all you need to spend if you're disciplined. :)
CPFs are also really great if you want to line dry. Since they "unfold" as opposed to fitteds (where the highly soaker is integrated into the diaper), they dry much more quickly.
Given you are in Japan, I'm not sure about good sources for you. Many of the places that we order from in the US do not do international shipping, sometimes not even to APO addresses.
I would write a few of the well known diapering ordering places and see if they will accommodate you.
EDITED to add: Just found a discussion on the Mothering diapering board about cloth diapers in japan. Apparently you can get them pretty inexpensively there: http://mothering.com/discussions/sho...l+and+shipping
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)