Romaji - Hiragana - Katakana
Seion
a i u e o
ka ki ku ke ko
sa shi su se so
ta chi tsu te to
na ni nu ne no
ha hi fu he ho
ma mi mu me mo
ya yu yo
ra ri ru re ro
wa wo
n
Dakuon
ga gi gu ge go
za ji zu ze zo
da ji zu de do
ba bi bu be bo
Handakuon
pa pi pu pe po
Yoon
Seion
kya きゃ キャ kyu きゅ キュ kyo きょ キョ
sha しゃ シャ shu しゅ シュ sho しょ ショ
cha ちゃ チャ chu ちゅ チュ cho ちょ チョ
nya にゃ ニャ nyu にゅ ニュ nyo にょ ニョ
hya ひゃ ヒャ hyu ひゅ ヒュ hyo ひょ ヒョ
mya みゃ ミャ myu みゅ ミュ myo みょ ミョ
rya りゃ リャ ryu りゅ リュ ryo りょ リョ
Dakuon
gya ぎゃ ギャ gyu ぎゅ ギュ gyo ぎょ ギョ
ja じゃ ジャ ju じゅ ジュ jo じょ ジョ
ja ぢゃ ヂャ ju ぢゅ ヂュ jo ぢょ ヂョ
bya びゃ ビャ byu びゅ ビュ byo びょ ビョ
Handakuon
pya ぴゃ ピャ pyu ぴゅ ピュ pyo ぴょ ピョ


Some resources:

- Stroke order for Hiragana, Katakana, and Kanji in the Japanese Language Proficiency Test

- Audio for Hiragana and Katakana

- Audio and stroke order for Hiragana and Katakana

- Mouse over audio for Hiragana and Katakana

- Flash practice for Hiragana and Katakana

- Javascript practice for Hiragana and Katakana

- Listening test for Hiragana and Katakana

- Flash timed test for Hiragana and Katakana

- Java test for Hiragana and Katakana

- Flash flashcard and multiple choice test for Hiragana and Katakana