Here are some tips from my time learning to get the rf24 radios to work.
If you read and, closely, follow Robin2's simple rf24 tutorial you should be able to get them working. That tutorial sure helped me. The code in the examples has been proven to work many many times. If it does not work for you, there is likely a hardware problem.
Run the CheckConnection.ino (look in reply #30 in the tutorial) to verify the physical wiring between the radio module and its processor (Arduino). This is especially useful if all you see is “Data received” repeating much more quickly then there is a problem - most likely theArduino is not communicating properly with its nRF24.
Make sure the rf24 power supply can provide enough current. This is especially true for the high power (external antenna) modules. I use homemade adapters like these. They are powered by 5V and have a 3.3V regulator on the board. Robin2 also has suggested trying with a 2 AA cell battery pack.
If using the high powered radios make sure to separate them by a few meters. They may not work too close together. Try the lower power settings.