I can't draw at all, so it is with a great deal of envy that I look upon works like those of Dmitriy Prozorov, also known as "Tamplier", who is the subject of a feature over on the official site. Winner of the Diablo III portrait of a champion art contest for his exceedingly cool barbarian, there are a lot of excellent works showcased, including an absolutely stunning Maiev Shadowsong, a brutal looking tauren warrior, and several Diablo III angels, including the Imperius shown above.
Head on over to the official site now and take a look through Dmitriy's body of work. It's quite impressive. Seriously, check out that picture of Maiev.