Tamer, I love questions!
In answer to your first question about printers, I use an Epson All-in-One DX9400F. As I work from home a printer-Fax-Scanner combination suits me best, although I'm not sure if it's the best printer for the job.
It uses a 4-ink cartridge system so it can be very pricey printing off loads of decal sheets. I'd look at printer reviews for a combination of the best colour rendering versus cost per copy. I used to print the decals in the highest quality setting, now I have reverted to the standard setting, and I haven't really noticed a significant drop in quality but the print speed has increased massively and I use far less ink per copy.
The key to saving money is to print just what you need. I once built one of Niub Niubs Death Star's and had loads of wasteage, now I am far more careful.
Re the second question: It's funny that you should ask me about a Hoth Diorama because that was what got me into all this stuff right from the start. A couple of years ago I saw "The Professor's" hoth Diorama over at Yakface
here is the link: http://www.yakfaceforums.com/phpBB3/viewtopic.php?f=25&t=589 . He used polystyrene packaging to build what I consider the best diorama ever created for Star Wars figures. It may not be the most accurate or technically challenging piece, but for sheer ingenuity and "I want one of those" factor, it wins hands down. I've never seen better.
Unfortunately I don't think it would be possible to recreate the Hoth setting using flat surfaces, snow and ice require texture and I wouldn't even attempt it with card or foamcore.
As a rule I make stuff that can be stored out of the way, all of my stuff folds flat and lives in the corner of my office now, a Hoth playset would demand a large space and so I would have to hand you over to The professor for inspiration.
I'd love to build a Hoth Set one day, but I'm having so much fun with my novel that I suspect you'll be seeing me here for many years to come doing much of the same stuff I'm doing now. A bit like those guys who, after 10 years are still working on stuff for X-Wing Alliance.
As always Tamer I am so grateful for the opportunity to display my work here and it is a total pleasure to be in everyone's company here. I am only too happy to answer any questions...
Jules