Is it possible to send out a certain email only if a product from a certain category is purchased? If so, what's the best way?

I don't use it but I believe that you can only do it at product level - suggest you explore:
 
Administration > Products > Top > Hair > Category > Edit Product ... selecy the Notify tab
 
It says it is for user notification but I believe that if you enter your e-mail in TO then you get the notification - you could send to customer and cc to you.
 
Hope that gets you off in the right direction.
 
Chris

Yeah I saw that. Was afraid that's the only way; it'll be messy to add the same email to every product (nasty data repetition) but at least there is a way I guess. I might get my hands dirty in the code and see if I can hack up a solution.
 
Cheers for the reply.

Or ask Viart for a cost to do this for you so that it remains compliant in a future upgrade?