I was thinking that Katagiri (www.katagiri.com) used to have an actual catalog they could send through the mail. I think I had one at one time. I don't know about the use of money orders, though. You should probably try to contact them, or any online Japanese grocery you want to use, and ask them about it. Katagiri has been extremely helpful to me in the past.
Hey Rach!!! What are you doing? I'm fine. I found a couple more to now that I looked at there websites close that you can use money orders =). I'll be on more soon when I get myself a new computer the other ones caput! =(
Echo the request and ask if anyone knows where to order dried fish. I bought some at Shirokiya when I was in Hawai'i and can't find anything like it here in Massachusetts or New York.
Some stuff can be found here: http://www.jlifeinternational.com/Catalog/Food/food_e.html although mostly snacks (usually essentials to most).......
In Massachusetts, you can try calling Yoshinoya (617-491-8221) or Kotobukiya (in the Porter Exchange Building/Cambridge).
Good Luck!