An item price notification system automatically interrogates product labels to determine product, pricing, and other unique data. The system uses a radio frequency (RF) radio frequency transceiver to generate an RF field to communicate with radio frequency identification (radio frequency transponders) transponders mountable to product display shelves. The radio frequency transponders contain information such as pricing information, nutritional information, and other unique data about the various products. As the RF radio frequency transceiver moves into proximity to various radio frequency transponders for a variety of products, the unique data are received by the RF radio frequency transceiver and are displayed for the user. The displayed data allows a user to make comparisons between products, and the system display and memory allow a user to store the unique data for those products and to make instant and cumulative product, price, and other comparisons.