They have dictionaries that are in alphabetical order, Ceewan. They're in Japanese alphabetical order, but that's the point. The order for commonly-used letters is something along the lines of:
あいうえお
かきくけこ
さしすせそ
たちつてと
なにぬねの
はひふへほ
まみむめも
や ゆ よ
らりるれろ
わ を
ん
I'm typing that from memory so I might have gotten some of the rows switched around, but I know that it's right for the most part. It always goes *a *i *u *e *o, where * represents whatever the consonant sound is. The first row begins with the pure vowels (Ah, Ee, Oo, Eh, Oh), the second row begins with the first of the consonants, which is K (Ka, Ki, Ku, Ke, Ko), etc.
As for voiced sounds, those come up alongside the appropriate letter. So for example, in the row:
かきくけこ
If I wanted to look up the word 月間 (gekkan, or げっかん), it would be in the same area as all the ones which start with け (Ke). Specifically, if there was a word kekkan (and there is, 欠陥), that would be immediately before gekkan. And the word after gekkan would probably begin with けっ , げっ , けつ , げつ , or (if we used up all of the Ke + Tsu combinations) a word beginning with けて.
This is probably way more than you wanted, so if you skipped to the bottom,
never fear, just click this Amazon.com link! ^_-
http://www.amazon.com/Kodanshas-Furigana-Japanese-Dictionary-Japanese-English/dp/4770024800
I own this book. I would say it's not worth the money if you're planning to take a course in Japanese at college or if you're already at an intermediate level of study ... but if you're a total beginner and are either going to be self-taught or are hoping to pick up while backpacking in Japan, then it might be a good resource.
Orrrrrrrrr, you could look into digital alternatives for your much-lighter-weight iPhone, Nintendo DS, PSP, Blackberry, etc etc.