i have a macbook. i need to get the songs from itunes(or at least some of them) onto my phone.. i have the LG CU500V. i need to find a memory card by sandisk i think that is 512mb. if i want about 20-30 songs on it is that enough? also where would i get the card? also, how would i get the songs onto it from itunes off of my macbook?

THANKS A BUNCH