Southwest Gift Cards?

[disneyagain]

I'm considering buy SW gift cards to purchase the few extra points that I need for my trip and to pay for the other RT ticket I'll need to purchase. How quickly will the gift card be available to purchase the points/other ticket (does it come in an email, so I can purchase the day I purchase the card?). How quickly will the points be available in my account to use towards my flight purchase?

I'm thinking if I purchase the gift card with my SW Visa, I'll earn points for the purchase and then points for the (paid) flight - right?

Thanks!