unable to write to usb mp3 player - how to change permissions for a device

[Fun Kid]

Hello Ubuntu users,

Firstly, I must say that I was very excited to find an Ubuntu newsgroup.
There seems to be a lot of forums but not many newsgroups for Ubuntu and
its variations (Kubuntu, Xubuntu, etc.).

I am hoping to get some assistance in fixing the problems I have been
having with my mp3 player - Rio Cali.  So far I have gotten my system to
recognize my Rio as a usb device and have been able to mount it without
any problems.  I can read from it but I cannot write to it.

A basic web search led me to believe that I don't have the right
permissions for my drive.  But unfortunately, I am very new to Linux
(and Ubuntu) and cant make any sense out of the instructions on some of
the websites.

I would like to be able to write to my Rio as a user (without requiring
to be the root user every time).  I would greatly appreciate a response
which contains step-by-step instructions on the fix.

My operating system is Ubuntu 6.06 (Dapper Drake) and I am using KDE as
my desktop.

Thanks in advance.
Funkid

PS:  My eventual goal is to be able to connect to my Rio using amaroK
and sync up my songs just like I used to do with my Rio and windows
media player (WMP).  At the moment I am unable to and I suspect it is
because I do no have the right permissions (as a user) to access the Rio
from amaroK.