go to to this site to earn points by doing tasks to get amazon cards to redeem and use to get guitar stirngs or stuff from amazon.

instaGC.com was created in February 2011 and is the top rewards site that offers instant gift cards to its members. Over 100 different options are available (example of a few -> Amazon, eBay, League of Legends, Pizza Hut, Target, Walmart) that you can redeem your points for. Tons of easy offers available with new ones added daily. There are daily, weekly, and monthy offer and referral contests as well.
or you could buy one less six pack a month and have the extra cash. (just seeing if anyone is paying attention)