Im still relatively new to this game, but i looked through a majority of the packs, and i want the White-Black lightsaber crystal, but when i go to find the pack in the Cartel Market, i cant find the pack at all, there seems to only be a tenth of the total packs in the Market, i was wondering why and how to get access to those packs?

old packs are embargoed (removed from the CM) after a short time, thus the only way to get them are off the GTN or wait for them to return to the CM as part of a short term promotion. If you are looking for something specific best bet is buy off the gtn. If can't afford it, you can buy/sell packs/hypercrates or run dailies until you can. They also run periodic "grand acquisition packs" that contain rare/super rare items of a specific type (mounts, crystals, gear etc.) keep your eye on those.

 

other than that you are probably out of luck.