So, you've found a new player, someone you don't know well or perhaps don't know at all. You have a slot in your ongoing campaign. How do you do it? Do you make sure she's a good fit before inviting her for the long term? Does everyone at the table have a say, or just the GM? Etc.
I normally follow this process:
- Check with the existing group
- Get everyone to meet somewhere neutral (coffee shop/pub) for lunch/dinner
- Check again with the existing group
- Sleep on it
I think it is important for everyone to have a say because the game does not belong to the GM but the whole group.
In my groups, the GM decides who joins and who does not, according to his plan. He is a very skilled person, who used to handle three parallel campaigns a week, each one with up to 13 players simultaneously without any issue. We know each other very well, so the issue of introducing a new person generally does not hold, however, it occurred occasionally that a completely new person joined the group. In any case, if he accepts the person, he asks the players' opinion first in any case.
For inexperienced players, the best strategy is to invite them first for a neutral session, he just watches the game as it develops, and the master keeps him involved by letting him throw dice, check manuals' pics, or discuss with players for optimal strategy. If he likes the idea, he can make his own character during a private session with the DM, and join the following meeting. We introduce players always at 1st level, even if the group is advanced (up to 10th level). The master tries to be kind, and generally a 1st level character gains levels fast when out with a 10th level group. We want characters and players to develop an intimate relationship. A 10th level character developed out of thin air is an impersonal being with an emotionless backstory, and in any case it would be overwhelming for a beginner player.
Everyone should have a say this is a group game. So introduce the person, let them see what it's all about and how you play.
A good fit? everyone has something to add to the game, as long as they are committed to the game I don't know if there is a bad fit. There is a 'role' for everyone. (unless they are a complete jerk or something)
As far as in game meetings meeting in a town, or saving the new character from an overwhelming battle work for me.
I agree with the notion of getting together in a non-gaming setting to see if you all like each other as people before sitting down to play games together.
If that is not possible though, this is the way our group used to do it.
The GM had the final say on offering an invitation to game with the group. If the GM chose to do so, the new player would be invited to play for one or two session on a trial basis. After that, the GM took a poll of the players to see if the new person was working out and said new person would stay or go based on the group opinion.
First of all, do some chatting via email and get a sense of a person. You don't need to know everything about them. You are meeting to play a game, not start dating.
I don't necessarily think you need to "go have coffee" together first- that can be fairly awkward. If you are meeting just to play the game, I think it's just woerd to have to jump through a lot of non-gaming meetings first.
Play in a public setting- the gameshop, someplace you can leave if it's not a good match-- to see how this person reacts.
Then if you like how it is going, reschedule something more, and if it isn't a good match, well, no big deal.