Need help with Ad network or Ad exchange programs

Hi;

I am new to online advertising, can someone please guide me as what price should be charged for advertising online like banner ads, text ads, image ads etc. How can i earn money with PPC, CPM, CPC?? what are the best platforms to register with??

Can someone also guide me to ad networks, as i am looking for database of websites that allow to publish ads

Thanks in advance guys

regards