The Wikia Welcome tool is an automatic process that helps wiki admins to welcome new editors. The goal is to show new contributors that there's a community on the wiki - and to help connect them to admins, so they know where to go if they have questions. When a contributor makes their first edit, the Welcome tool leaves a talk page message for them, and creates a user page.
The talk page message is signed by the admin who edited the wiki most recently - this is to help the contributor find someone who's available to talk to them if they need it. If no admin has recently edited, the message will be signed by a member of the Wikia Community Team.
Finding the new editors
Assuming they don't find you first, there are two simple methods you can use to find new users:
Welcome messages are created by User:Wikia - you can check that user's contributions to see who has been welcomed recently.