if you email Sheri Crabtree
at sheri.crabtree@kysu.edu and ask nicely she will probably send you a packet of seeds, be sure to keep them damp and cool for a few months before planting.

it is also worth mentioning:

paw paws germinate pretty easily, but set a huge tap root before the seedling emerges, so be patient, the seedling may not emerge from the soil until june or july.

because of that taproot it is best to grow them in very deep pots, if you are just growing a few 1/2 galllon milk/juice jugs/cartons are good, if you are doing a lot i like 12" treepots.

Pawpaws produce best in full sun, but young trees require some shade. You can plant tall plants around the seedlings to shade them (and then move them away later) or use artificial shade like a bluex growtube or tomato cage covered in remay/shade cloth.

If you are wanting them for edible fruit, you might consider buying grafted cultivar plants. Fruit of cultivars like 'Levfiv' (Susquehanna), 'NC-1', 'Overleese', and 'Wansevwan' (Shenandoah) is quite a bit better than what you would typically expect from seed-grown plants.