We are working to make a lovely NeoHtml guide right now!  
But in the mean time please check out these helpful sites 
to get you started!
<p>
<a href="http://home.neopets.com/templates/homepage.phtml?pet_name=card_captors_sa89">How to customize your Fonts</a> By Chobit203
<br>
<a href="http://home.neopets.com/templates/homepage.phtml?pet_name=yogi596">How to make a Blog</a> By Sweet_sour666214
<br>