We barely play anymore, so if you're buying just to play with us, well, you'll be a little disappointed.
Anyways... The easiest way to go is to find the Diablo Battle Chest. The Battle Chest is a bundle, at a fairly good price at EB too, that includes Diablo, Diablo II, Lord of Destruction, and a Strategy Guide. Since a new patch came out though, the strategy guide might be a bit outdated. We play on Diablo II Lord of Destruction, realm USEast. Lord of Destruction is just the expansion with two new character classes and another act to quest in. Nonexpansions can't play in game with expansion players.