You need to report him to as many people as you can find to report him to.
Council for parking,
Water company for filling up vans from home, they will more than likely be bothered about it if he is not paying business rates, get someone there to check it out. (There will be a big difference in his business and domestic rates),
Council - if he is running a business from home get them to check he is paying business rates for council tax etc. If his bins are collected at the same time as everyone else's by the same bin wagon he might not be paying business rates.
Is there a way to check what regulations he has to follow if running a business from home? Often there are rules about not causing problems for neighbours with parking, noise nuisance etc.
I remember a thread within the last couple of years about a poster coming home early from work as they were ill only to find a strange car parked on their drive. Turns out a (obnoxious) neighbour over the road was running a dog grooming business from home, part of the conditions was about not causing problems for neighbours parking wise. Because the road was full he'd told the clients they could park on the posters drive. He still did it after being told not to. Eventually the council withdraw the permission to trade from home, he closed the business and ended up moving.
If your neighbour is not running a business from home they should not be using their domestic water supply and should not be parking a commercial vehicle on the road afaik. They should apply for a license to do so, part of which will probably be to follow certain guidelines.
If they are registered as running a business from home they should have regulations they need to follow. If parking is not included in that then you can complain and see if you can apply to have it put in.
You could report him for everything you can think of if you think he's not doing it correctly/lawfully, or you or your dh (depending on who he'd be more responsive to) could discuss it with him. Ask about how you get permission to run a business from home, permit for parking/what commercial vehicles can be parked without permits, etc. If it looks like he's not doing things correctly you/dh can use it for leverage and drop into conversation that you'd not report possible problems if he'd stop blocking you in if you're willing to go that route.
Personally I would want the business checked out if there were any doubts about how it was being run, if he's cutting corners/not paying what he's supposed to for one thing it is likely there are other things not being done correctly. If so, if he has business insurance (might need checked out too), and he has an accident that affects you or his neighbours, if it is considered to be because he wasn't doing something correctly the insurance might not pay out.
It might 'just' be a simple parking/disrespect problem, there might be many other things wrong under the surface though.