Try this for reading recommendations:
http://www.whatshouldireadnext.com/books/search
And I just learned a few days ago how to spend that big micropay balance. You go to your settings and select for it to spend micropay first. Then it goes throught the checkout process and I didn't see a difference, seemed like it was coming from credit card. However, the receipt showed a micropayment and my remaining total micropay balance.