Usually around 24 hours is the grace period for getting your thread approved. That gives the mods enough time to sign onto the forums, check for any unapproved threads, and then see if the threads in question fit the rules.
If it has been more than 24 hours since you've posted your thread, and it hasn't been approved yet, feel free to send a private message to the moderator(s) of the section about it.
If it has been more than 24 hours since you've posted your thread, and it hasn't been approved yet, feel free to send a private message to the moderator(s) of the section about it.