HeartGold and SoulSilver hit shelves on 2/10/2010 and should be at a retailer of cards near you. If you haven't already went and picked up some packs I'd suggest you do so. I bought 8 packs, Aaron bought 8, and Lauren bought 4. The Pokémon Prime seem to be relatively easy to get compared to other powerful pokémon for earlier sets (EX and Lv. X).
I pulled from my packs a Donphan (Prime) and a Meganium (Prime) as well as several good holo rares. Aaron had a better haul getting a Feraligatr (Prime), Ampharos (Prime), Blissey (Prime), and Lugia LEGEND piece plus several holos. Lauren got a Meganium (Prime) and some holos. So, out of 20 packs combined we got 7 Prime/Legend cards... which is pretty good. Lv. X cards are roughly 3 per box, meaning you would have to buy 36 packs to to get 3. In the case of HG/SS cards, you get a really good card roughly 1 every 3 or 4 packs. Also, Pokémon (Prime) take the place of the reverse holo in the pack. Because of this, you are assured to get another rare card as well in addition to the Prime. For example, I pulled my Donphan (Prime) out of a pack that also had the non-holo rare Donphan in it as well. Aaron pulled his Feraligatr (Prime) from a pack with a holo Arcanine also in it, and so on.