The slate should be :10 seconds long and usually has the advertiser, the ad agency, the date, the title, the iscii code and the copyright - followed by :10 seconds of black (or black and academy leader) prior to the spot. Yes, bars and tone are standard. Academy leader is not as critical as it used to be since all spots should start on the even minute and are cued up that way.
you should be asking your client for "delivery specs" because they usually vary to some degree. generally, though it's...
00:58:00:00 - black (30s)
00:58:30:00 - bars and tone (60s)
00:59:30:00 - black (10s)
00:59:40:00 - slate (10s)
00:59:50:00 - black (10s)
01:00:00:00 - program start
Delivery specs should be provided for you. But really, it doesn't matter. There is not right or wrong. The important things is that you clearly label on your specs or the tape the exact order and duration of things...otherwise you are going to piss someone off.
If you are delivering on DVD be sure to leave some (10 seconds) of black at the front and end of your commercial. Do as you will with the rest.
We always get amature productions on DVD that will start or stop the dvd right at the head or the tail of the show/commercial. This makes it VERY annoying to dub down to a usable format.