Point being, if you want to kill someone; you have to use your brain. Always make them think you are their friend untill the very last second. I personaly just res them afterwards and keep being their friend, Unless I have a real reason for killing them. Acting like the persons friend makes them more suprised when you do kill them.
Unless you are killing very low level characters or using hacks, then you will need to use a spell to kill someone. I highly recomend fireball. It's never let me down before. If your magic is high enough and you use the right items you can get this spell to do at least 400 damage.
From here simply get someone in the dungeon, away from stairs and TPs and when thier health is low blast the sucka! Then if you are nice like me you will res them and go about your buisness.
When killing someone in particular it's best to use hacks and trainers. That way there are no mistakes. Add your target to your friend list so you always know where they are. Next you should hack your level to match their's so that they won't get supisous when you join a game they're in. Make sure the hacks are on. The hacks that are the best ones to use that always come in handy are God mode, Anti-auto kill, F1 res all hack, and most importantly Auto Kill (AKA player cursor kill) which allows you to kill people just by holding your pointer over them while in the dungeon. Auto kill can also kill people who have god mode. When you use auto kill it's good to use some spells on them so it looks like you killed them legit. This will decreas the chances of the idiot yelling "You are a hacker!".
If you are killing someone in particular like one of the people on the enemy list you should take a screne shot of their dead body. This is because ears can easily be faked or gotten by chance (just found them lying around from when someone else killed the person). To do this you just hold your pointer over their dead body so that their name is displayed at the bottom of the screen and then hit the "Print screen" key on your keyboard (the key that should be just above the insert key and is next to the scroll lock key). A picture of the screen will then be automaticly saved to your diablo folder which should be located C:\Diablo. It will be a paint document. Next just e-mail it as an attachment to the person who wanted them killed. This is how REAL bounty hunters on Diablo do it. The person may leave right after you kill them so you have to be quick and don't be afraid to hit the print screen button as many times as you want so it will save multiple screen shots and you can choose the ones you want to e-mail. And always be sure to say something like "You shouldn't have @$#%ed with 4HA!" just as you're about to kill them. If you want to be a bounty hunter you should apply these tactics. To become a bounty hunter just put in your profile (double click your name while in chat) that you are a bounty hunter and that you are for hire.
There are two types of friends in Diablo. Game friends and chat room friends. A lot of people on this game dont play the game at all. They just linger in the chat rooms making wierd key faces like =.= and >.> and my favorite <('.'<). But they are good people to know when all the games are laggin or you just feel like talking. I dont't know exactly how to make friends with these people but joining in the conversation and typing lol to all their jokes helps.
In a game is even easier to make friends. When you start out in town find someone who needs an item or wants something duped and try to help them out, or at least act like you want to! Then just go lvl up with them for a while. Then when you think they are ok tell them that you are adding them to your friend list (see tips). They will probably add you to their's too. And you made yourself an ally.