That's a fairly broad question.
Do you know what specifically you want to get out of the test, and what sort of application you will be using ACT to test?
I personally have not been able to find any resources on the Net that really give much information or tutorials on ACT use or ACT script development, and so I've been working mainly with the ACT help file and general VB/VBScript resources.
The applications I test mainly are Java servlet applications running under IPlanet, WebLogic, and JServ/Apache, the user authentication is form-based rather than NT authentication, and other than general stress testing, we do specific by-hit performance evaulation and screen verification...so if you're looking at some of those areas, I might be able to help.
I prefer 'maliciously mischevious'.
TDAdmin of Evil