a quick check of NB shows they are in fact not selling at this time, but Freshops Rhizome Varieties
seems to show that they are.
now that i'm not drunk and can process information correctly -
don't let home-grown hops factor into your calculations when deciding whether you want to homebrew or not. at least for your first few batches, you'll want things as simple as they get, and that means hop pellets. when you're trying to refine your technique to make GOOD beer, you want as much consistency as possible - that means the only thing that should be inconsistent is your technique - which means your ingredients should be high quality. use a good liquid yeast (XL smack packs from Wyeast, or tubes from White Labs), excellent malts (start with extracts, not grains), and consistent hops (again, pellets). the alpha acid percentage of your fresh hops would be all but impossible to determine, and that's an important number for a young brewer.
besides, you don't want to waste your fresh hops in the bittering additions, you want to use them as aroma additions or dry hopping.
so, in short (damn, i still sound drunk, that's not good):
go learn to brew beer with hop pellets. plant your rhizomes. if you brew once once every 8-12 weeks, you'll be ready to use them by their second year