No, alternating books and magazines on a shelf is not considered cross merchandising. Cross merchandising typically involves displaying complementary products together to encourage additional sales, such as placing wine and cheese near each other. Mixing books and magazines on a shelf may simply be a way to organize different reading materials.
There are many sites where companies advertise their jobs upon. Two popular names are "InRetail" and "Monster". These two website take your information and store them in a database, you then can use their service to apply for jobs advertised upon their website for your benefit. If you have your CV up and it is appropriate, a employer might just pick you.
IRC is an instant redeemable coupon or instant rebate coupon. These are often found on the shelf in front of the product, attached directly to the product (peelies), or somewhere else in the store (ads, coupon books, etc).