Calling a webservice as part of a Process Author workflow?

Hello!

I'm quite new to SugarCRM.  I'm trying to see if the Process Author (aka Advanced Automation) would work for us.  When a lead is promoted to an account, I'd like to call an internal webservice to do additional work - such as provision a demo account, etc.  I was looking at the "actions" widget within Process Author, and the action types include: Business Rule, Assign User, Round Robin, Change Field, and Add Additional Field.   Business rules seem like reusable chunks of logic, so those probably aren't it.

Should I be looking at logic hooks instead?  If so, is there a way to trigger a logic hook from the Process Author?  (I hope that makes sense!)

Thanks!

Bret