Credit Card Programs - Costco gift card

If I purchase a costco gift card (online) using my Citi AAdvantage Visa business card will the $ amount of this gift card be applied towards my $3000 spending requirement?

Yes, it will.

Keep an eye out for costco cash cards at Plastic Jungle. Last week they had them for $98 per $100, plus you can get 4% via topcashback.com at Plastic Jungle. Needless to say the 300 cards sold out quick.