Mac Newbie need kickstart

I know I know!
You hate this stupid newbie questions :smiley: But I need just a quickstart to know what itā€™s all about. ( I have been looking arround the docs)

So:
I live in Cyprus and have a Swedish VoIP account (telephone number) working great here in Cyprus.

Now I was looking for a way to also use my local mobile phone (or any phone) to make my computer like a clever automatic switch board.

I want to use my mobile calling my local home number which is connected to my computer. Then Asterisk gives me a new dial tone from my VoIP account and I can dial the Swedish number in Sweden through my VoIP account. That would save me tones with money :smile:

(I hope some body could understand that, hehe)

My question is:

I only use and have Mac computers, so is there any hardware for Mac or could I use the internal modem to plug the local phone to my Mac?

Is Asterisk a ā€œmust know UNIX programā€ or is there simple GUIā€™s?

Thanks for any help guys!!!