Hi

You can certainly buy the paper charts (High Level enroute charts are what you want) at any aviation retailer. I'd post a link but not sure if that would count as advertising...

Alternatively I think there is an add-on to google earth that includes airspace, you might want to search for that.

Found it - have a look at http://www.lloydbailey.net/airspace.html. I've only downloaded the UK one but presume the one for the US works as well.

cheers