How do you receive and send pictures on iPhone?

Through email only. On the newest version available on June 17, you can receive them through MMS.

all you have to do is go to www.tuaw.com and type in i phone or your question in the task bar and it will explain everything

(january2010)

There are also some applications of third parties available on Apple appstore that can share files (photos, etc.) between 2 iphones (3GS) via Bluetooth. some of them are free and others not.