Hi SLD,
I would suggest that you firstly make a list of everyone you owe money to (regardless of it being a £1 or £25,000) and then sit down and make a list of all your essential outgoings as this will help when you contact someone.
As Melanie said the HP may or maynot be included into the IVA depends on the type of agreement you entered into so you may want to find out the agreement. Who is your finance company ?????
Once you have this info i would then visit
www.iva.com were you can view all IPs and firms and research a few from there, once you have found 2 or 3 you are happy with give them a ring.
Never agree to anything on the first call, speak to a few then make a list of all the questions you have got - once you are happy and comfortable then proceed.
I would perhaps use this website to get other peoples views on the company first.
Good luck