1. is legal? 2. can i sign up to download itunes and buy music from the store using the itunes gift cards (at my retail store it sells itunes gift cards = $20, $40, $50, $100)? i don't have a credit card

Yes it's legal.

Yes you can use giftcards for Itunes.

you pop on, search for a song, click download. And it will charge your card, I use a credit card but I assume they have some means of redeeming or charging your Itunes card.

Edit: looking at my Itunes, it says you don't need a credit card to redeem a gift card, you just have to enter your gift card's info. 

1 duh
2 yes, but just use Limewire (its free)

Limewire is free but to some extent it is illegal......Just to let you know...;)

Yes, it is Legall
and yes if you don't have a credit card then yes, use the ITunes Giftcards
i heard that u can get them at costco for cheap like 5 bucks off

how much does itunes and limewire and other file-sharing programs effect the music industry?

the music companies has to authorise the music rights to companies like itunes don't they?


also with itunes if you buy a $100 gift card to register and download songs and it runs out how do you recharge? obviously you buy a new gift card than what else happens?

1. Yes it's legal.

2. iTunes Gift Cards FAQ: http://www.apple.com/support/itunes/store/giftcard/