I got a 30 day trial from
www.adobe.com/acrobattrialThe designer came as part of the download and is perfect for evaluating how useful it's going to be.
Must say though - as I don't know much xml or html some of what's available is lost on me i.e. it all works fine on my pc with the trial but our corporate standard is Acrobat Reaqder 6 - my first test of the e-mail submit button on a user machine did nothing.....
Back to the drawing board for me but the 30 day trial is extremely useful.