Advise for my new I Mac, I need Midi and audio help Options

[mtrev]

I have recently bought a new I Mac 700 MHz, and am anxious to make some music with it...I need some advise.

I want a program to compose and arrange music...I want to use my synthesizer via midi, as well as use outside audio like voice, guitar, sound loops etc...
I want to be able to manipulate sounds, cut and drag, and notate.  I also want the capability to receive audio from my mini disc player.  

I have been researching Cubase and think it would be perfect.  Any thoughts on this program, and whether it might be right for me?  Which version?  

Would I need to by a sound card as well as the software?

I know I have a lot of questions, but ANY advice and/or wisdom would be much appreciated...

[bachaboulou]

i use same machines (imac g4, minidisc, midikeyboard...)
i made three partitions on my hd (5giga for os9+softs, 5giga for osx+softs, 30 giga for documents)
i only make music on os9 [protools free, digital performer3, reason, T racks], osx is not ready for it (wait for jaguar [osx.2] and, if i may, don't use cubase if uve never used an audiosequencer before, this one is not the easiest to handle)
if u have 500$, get an Mbox (digidesign): soft=protools le [24 audiotrax+unlimited miditrax], usb hardware interface.
if u have 1000$, get a motu 828 : soft=digital performer 3 [unlimited audio & miditrax], firewire hardware interface
if ure poor like me at the moment, prefer edirol ua-1d [129 euros] (usb>optical&coaxial) to exchange audio data from minidisc to imac.