In ARM based devices things are not so flexible as in x86. Normally the installation process varies a lot from device to the device. They can be based on USB vendor software, install a special bootloader on the sdcard (xloader or uboot) and press a key combination to boot from sdcard ... etc.
I would recommend you to try find someone with the same device that has already replaced the Android for the Linux on your device or get a device in which people have already done that.
Replacing the Android for Linux is not simple, varies a lot and will be a pain to get all drivers working.
As an example:
http://www.youtube.com/watch?v=40HetOQ0dQA