If you have a question about a post, just flag the post.
If you have any other questions, the easiest thing is just to send us a private message.
If you want to send a message to multiple moderators, once you bring up the message box for one moderator, click on the plus sign next to the “To” field at the top of the message to add the others.
Each forum (category) has a sticky at the top of it that contains a list of all moderators for that forum.