Arduino Uno + Ethernet Shield + wireless transmitter (both on SPI bus)

Projects General Guidance
2
  1. The ethernet shield uses 5V for power, right? Does it get that power from the 5V pin along the sides or the ICSP header? Sparkfun notes say the ethernet shield uses the ICSP header, but the ICSP header doesn't have 5V power. Trying to understand how it's designed.

The ICSP has the SPI data lines (MOSI, MISO, and SCLK), 5v power, GND, and RESET.

  1. Can I use the ethernet shield's female headers almost like a prototype shield? That is, connect the wireless module's SPI wires (Device Select, MOSI, MISO, Clock) directly to pins 10, 11, 12, 13 on the Ethernet shield?

If it is an Uno, yes.
If it is a Mega, no.