I was looking information about buying Bitcoins, and I found out Bitcoins can be bought only using sites which offer this kind of service. How can I buy Bitcoins without using those sites? There should be another method, based on the P2P network of Bitcoin. Besides, those sites offering exchange of money, which means replacing my money with existing Bitcoins, and not creating new Bitcoins.

Why do sites prefer to deliever a group of transactions and pay a fee and not to transfer it one by one?

I've got 0.00002 BTC from CoinAd.com a few hours ago, but it's still unconfirmed, according to Blockchain.info. What can I do? What happens if it stays unconfirmed?

I recently started to earn money online, but as I see it, those sites let you earn a very low amount of money (duplicates of 0.01 mBTC), but I've seen in Blockchain.info's history that people are earning huge amounts of money, from tens of BTCs to even 500BTC. How do they do it? Provably not using mining, otherwise they won't be using Blockchain.info, or they are only using it to transfer money anonymously? Of course that in most of the transactions you will see only an address, and not who owns it, besides a few sites that Blockchain.info knows their address, so these records doesn't really help me, also because there is no way to contact the owner of the address.