Top left corner has the HELP option you can click.
http://www.bonanza.com/site_help
Here is more on fees:
http://www.bonanza.com/site_help/general/pricing?title=Bonanza+Pricing
And here's a short list:
7 great reasons to sell on Bonanza:
Free listings Its free to list on Bonanza. Yes. Always.
Low fees Sold an item? You keep about 97% of the money.
Free distribution Every item you post is sent directly to Google and Bing.
Free sales consultation We have real humans available to help you sell, fast.
Checkout options Use PayPal, Google Checkout, Checkout by Amazon, or all of the above.
Bonanza-only features Every store has built-in chat, customization available.
Relentless simplicity We obsess over "the small stuff" to keep selling painless.
Hope this helps! Bonanza is awesome!