Dear Kate, I do not know about e-prime. But have a look at SciCovery.  I think this is the future for this type of experimentation. Easy to program and you can do the experiments worldwide. Best Peter

p.s. I'm part of that company, explaining my level of enthusiasm. :)

https://www.scicovery.com/

Thanks Peter, I liked the idea of scicovery.

And, Kate, psychopy [http://www.psychopy.org/] builder has stroop task already designed in its demo package. You can play around within to design a vigilance task, it is very simple. It is free and open source and does not require any programming skills (well very little if you need to make complex tweaks-which you may not need ).

Hope that helps

Hi Kieran, thanks for the reply but I've actually already created a Stroop and Vigilance task on the program. I was after a task using both auditory and visual stimuli and the same time but think I have settled for a Dual N-back 2 task. Thank you anyway.