Readers are cheap, around 10 bucks for some models. I'd just get it over with and pick one up now, you'll most likely need it if you're going to be transferring alot of data to and from your SD card(s).
You can use a utility called
Storage Tools, or
Pocket Mechanic to format SD cards on the Axim.
I highly recommend Pocket Mechanic for alot of great things other than it's SD modules. Give the trial a shot and see what you think :)