Just went down this road 3 weeks ago...First thing is get on line to
http://aus.us-visaservices.com .. There you will be asked to give them your visa number to obtain a booking some two weeks ahead... Fill out the online application, pay your $130 fee at a post office and keep your reciept. Some very important notes,
1 You must provide two photo's of yourself in VISA size. Not passport size.. I saw the guy in front of me get kicked out of embassey for this.. Most photo shops have the correct format and know the drill..
2 If you are flying into the US you will also require the B1 B2 Visa. This allows you to train, and or coduct certain business within the states.. They will ask you at the embassey if you want a one year ( free) or a five year visa for an extra $30 bills ( Big decision ) You are NOT allowed to train within the USA if on a tourist waiver.
3 There is only on space on the "live application form" to select which type of visa, on Visa Pro. Go the B2 and ask for the C1 visa combination at your interview.
4 Make sure you have a letter from your employer explaining why you need the visa.
5 Don't bother applying if you have even the smallest of criminal convictions.. They queried me on a conviction I had in 1980 for "Riding a unlicenced trail bike in a national park"
6 Be prepared to allow half a day out of your life. They aren't very friendly there either.. Specially that big black guy
Hope this helps