Here's the background: I'm a freelance design engineer and model maker but I seem to be doing more and more graphic work. I use a lot of stock images but I always struggle to find ones that are just right. A lot of these are just backgrounds, eg leaves, brick walls, sky. I'm toying with the idea of getting a decent camera to take my own images. It would be handy to take pics of the things I make, too.
Cutting to the chase: I'm looking for a dSLR that'll take decent pics that can be blown up fairly big for printing. Can I get something without breaking the bank? Is there better bang-for-buck by moving away from the Canon/Nikon? I've seen some keen pricing on Pentax. I've got an LX3 for keeping in a pocket and taking general snaps so this will only be for occasional use and spend most of it's time at home.