Look! New Recipes! scans vendors when you browse their goods for any trainable item (recipes, plans, formulas, et cetera) and notifies you (via the chat window) of the ones you already know, don't know but can learn, and can't learn.

Once you talk to a vendor, if he has any trainable items, they will be displayed in your main chat window. Red items are items you can't learn yet (skill level inadequate, not trained that skill, et cetera) and green items are ones you can learn. Items you already know will be displayed in a darker color.