Be patient with your new toy -- it pre-dates iPods and such by a good number of years, yet still outperforms them all when working correctly. But it is a bit clunky when needing fixes and the like.
To do just about anything with it, you will need to acquire two items:
(1) a +12VDC AC-Adaptor, rated for at least 1000mA output. It needs a DC power plug on the end of it, 5.5mm x 2.1mm (the most common size on most good adaptors).
(2) a 9-pin F-F serial null modem cable. Absolutely essential. We cannot help you (much) without this item.
New/complete RioCar packages always have both of those. What serial number is your unit?
Cheers