did you try looking on usistd website?
they list requirements, trainers, and even have a page of 'tips'

HI,

All tips highly appreciated for a candidate looking to prepare for the ISTD associate examination. Is it very intensive and time consuming? Who to contact in the LA, CA area? Average cost?

Thankss much in advance.

The cost factor, is largely in your control.

I have to assume you are already teaching ?-- if that is the case-- then rev.techn. will serve your needs, and may be studied ( at no cost to you ) at your leisure.

Suggest , when you are nearing an exam date, to get someone to quiz you on some of the mans and ladies steps, varying their questions .. it is primarily ( at this level ) a memory test, although you will be required to show a competant level of dance .

examiners costs vary-- if you are part of a days work, will be less than employing one just for you . The exam time--- 60 to 75 mins. ( dont forget to include rhythm dancing in your practical if doing B/Room ) 65 % is usually minim. pass grade --- and by the way-- good luck !!

A while back there was a series of short articles written by Max M. Ali, M.D, under the name DanceMax. He described his experiences while taking the ISTD exams. Lots of good information, and it is interesting reading.
http://www.dancesport.uk.com/tid-bits/
Read issues:
174, 176, 178, 180, 182,184,186, 188, 190, 192, 194,196, 198, 202, 209