Japanese isn't normally written in all hiragana, except for books aimed at 4-year olds. 5-6 year olds have a handful of kanji mixed in - maybe just 人、木、 and 大 , but still; and as the recommended age on books goes up so does the kanji count. (I don't think there's any way to know which kanji, but it's probably similar to the graded kanji lists.)
I recommend installing the rikai-chan plugin for firefox or the rikai-kun plugin for IE that lets you see the kana of a kanji word on mouseover. (Also the english gloss from EDICT(wwwjdic) when you install dictionary files; you can toggle english terms on and off.)
Really, the only pure-kana text I've seen is in the first chapters of textbooks.
You get used to the lack of spaces as you get better with the language, and also the kanji help to put a shape on the sentence and to see where words start and end.
Edit: Just remembered, The JOI blog has a version with yomigana (kana following each kanji). Not pure kana, but the reading is there in parentheses:
Japanese teachers' audio blog-JOI Learn Japanese Online
nhk news easy has furigana (kana above the kanji),
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キッズgoo has okurigana too, just click the あり button after the word よみがな in the upper-right. (This is actually a page for Japanese kids so it's more than a little childish, and hard to navigate when you don't know Japanese well. Still, I used to read articles on it.)
Hmmmm. Still can't think of any pure kana resources.
You should check out Erin's Challenge though,
Erin's Challenge! I can speak Japanese. | The Japan Foundation you can get kana under the videos and maybe a kana version of the manga version of each skit. I forget exactly, but it's still an invaluable beginner's page.