The modules for controllers for storage devices are in the linux kernel. Assuming that the flash card is mounted as a storage device, there are no modules outside the kernel you have to incorporate into a live-cd. Using some newer linux live-cd that picks up the flash card, try the command "sudo lshw" to look at how the flash card is see, then use google and perhaps "lsmod", "lspci" or "lsusb" to find more information about how it is mounted in linux.
It is possible to have a module boot as soon as the kernel is invoked as part of the boot process, but that may not be necessary here and not what you are interested in.
There are guides to composing your own version of a Ubuntu live-cd, but the latest may not be applicable for the version of linux that you wish to use, that having kernel 2.6.21. One way of making a live-cd is to install and modify Ubuntu, then make the installed Ubuntu into a live-cd.
You don't provide enough information to give you more than a general answer to your question.