Most of the transfers appear at the start of recruiting period 2, when they are needed the most (at least according to the smoke in the forums).
Start by sending your assistant coach on searches, first close in and then gradually farther out, looking only for previously non-contacted players. Then FSS states that you haven't looked at yet. The transfers will be at the end of the list, with F's as their reported attribute values. They aren't actually F's -- scout the ones you might need a little deeper and you'll find that some of them are worthwhile. Good luck.