As with PAC, AquariumPlants.com has a great selection, but the shipping cost is a bit high IMO. I get my root fertilizers from AP; overpriced everywhere else.
Hans offers plants and so much more.
Yes to the AA classifieds!
I have always had good luck on Www.aquabid. Com lots of different sellers. Shipping always seemed reasonable and many sellers alloy you to combine fish with plants if you chose to. Just shop around. Lots of good listings!