I am a big fan of wallpaper because it adds such panache to the design of a space. It is one of the greatest design element I try to incorporate into any room that I can (including my own).
Although the options are almost limitless, I have a few go-to favorite companies, one of them being Thibaut Designs. Their styles run the gamut but their "forte" (if you will) is in the transitional genres and their price point in wonderful (that's very subjective, I know).
They have all types of wallpaper from vinyls (use mostly in commercial applications) to textured grasscloths (which has made a resurgence since the 70s) to embossed or flocked papers (again reminiscent of the 70s) to metallics (you know I love a little bling).
Here are some of my Thibaut faves: