Macbook Looping V rc-20xl

[Joshua Rothhaas <joshua.mr@gmail.com>]

Ok so i hear alot of talk about Laptop looping. I am a total beginner 
here and i was planning on soon buying a rc-20xl for beatboxing and 
vocal looping (i mentioned this on these threads before) what would be a 
cheaper and possibly easier start; the rc-20xl or a laptop setup.

Keep in mind i have a macbook, not a windows box, and have no supplies 
at all yet (no, mic, no amp, nothing, only a macbook, and a drive to 
start looping). If the laptop solution is viable, what is it? what 
software do i need? what kind of mic and midi pedals do i need? can a 
macbook with the 2ghz processor, and 2gb of ram handle the ordeal?

if its the rc-20xl what would i need? what kind of mic? an amp? can i 
route the sound to my computer speakers? can i record live on my macbook 
somehow?

So many questions, i know. Even a few answered would be fantastic.

Thanks all
-JoshR