I'm still not familiar with all the DLC missions you can get, but from my understanding, Arrival is the only one you have to purchase. I already got Zaeed and Kasumi as members.
Yeah, that's what I thought. I mean, I got mine new and had that. Though, I went and checked the Mass Effect Wiki and it said this on the subject:
"Copies of the PlayStation 3 version of Mass Effect 2 include the following:
The full Mass Effect 2 game
Blood Dragon Armor
Kasumi - Stolen Memory
Overlord
Lair of the Shadow Broker
One Cerberus Network activation code."
And
"These items are available for players to download upon activation of the Cerberus Network:
Normandy Crash Site
Zaeed - The Price of Revenge
Cerberus Weapon and Armor
Arc Projector
Firewalker Pack
Mass Effect: Genesis (PlayStation 3 only, Xbox 360 and PC owners must purchase Genesis separately)"
Hope that clears some things up.