The race of dragons are particularly malleable in terms of their anatomy, appearance, lifestyle and role. For mine I just decided to make it a (still fantastical-style) regular animal. I'd imagine this one as being somewhat sentient, but I just wanted something that looks like the sort of reptile that could possibly evolve over time. So I just based it on real animals (Komodo dragon body, crocodile scales and scutes and a ceratopsian crest (alternate angles of the dragons head exist in sketch-form, I'll have to upload those too)
Update: Here's the sketch of the dragon with the alternate views of his crest
For the owlbear, after looking at what other artists had done using my handy dandy Google Images search, I decided I just wanted to approach it with the idea that an owlbear is simply the largest and strongest member of the griffin family. So it's essentially just a griffin made out of owl and bear parts instead of lion and eagle parts.
Weta said all that needed to be said when it comes to dwarves (and pretty much everything else in fantasy), and their approach will never be topped. So I went a different way, starting with the question "what would a humanoid race look like if they've been living in darkness underground for millions of years?" Dwarves shouldn't ever just be little Vikings with geometric armor and houses ever again.
I'm not very familiar with doing non-linear, painterly stuff, so this was a great exercise for that and I feel like I'm getting the hang of it pretty quick. To help get started I followed Sam Nielsen's technique that he illustrates in this post from The Art Center http://theartcenter.blogspot.com/2010/03/sam-nielson-painting-process.html
It's a very simple, straight-forward, very well articulated technique and I was surprised by how FAST it made things go by. I was able to color and render the owlbear and dwarf pieces in around 5 hours