Platic bodies can feel remarkably sturdy these days. Just make sure the lens mounting plate is metal, though, as these wear with use. Plastic bodies are also much lighter and pro or semi-pro cameras which tend to have the best construction are obviously much more expensive.
TBH, it's horses for courses so have a think about what you want to do with it. Forget the specifications in most cases as there's very little to choose between them and they will all appear to take very good pictures.
It's the detail that matters, and what makes the difference between the cheap and the expensive in most cases - how fast and accurate is the focussing? Is the exposure spot on? How good does it "feel" to use? It will have loads of Megapixels but what's the image quality really like? Look at sharp edges in the picture for odd effects.
In other words, you need to have a proper play with one rather than picking one from a catalogue.
I must admit, I bought a relatively cheap DSLR (Pentax ISTDL2) 2 1/2 years ago on the basis that the bodies that had the performance I really wanted were still much too expensive and dropping in price, but that I wanted one to take on our Honeymoon.
I fully expected to still be using film for the stuff that mattered so I set off with the DSLR and a film SLR loaded with Velvia 50.
The results I got from a "budget" DLSR just blew away what I managed with slide film, TBH. I think my film SLRs have sat in a drawer since.
However, the auto focussing is not great on my DSLR, making it useless for photographing motorsport, for example. Horses for courses, as I say. One of these days I will treat myself to a really decent DSLR as I surprised myself with the one I've got.
Kevin