makes excellent trials bikes in pretty much all price ranges.
the norco that you linked to is a very nice bike indeed. it is a "stock" trials bike, meaning that it has 26" wheels, and a larger frame. it looks like a mountain bike, but the angles are a little steeper i believe.
a "mod" trials bike looks more like a BMX bike, but the frame is longer and a lot of times, the rear wheel is actually 19" instead of 20" and uses a super wide tire. mod bikes are more fun because they're usually lighter, and can fit into tight places, and are generally more maneuverable.
all that said, if you're just getting into trials, you don't need to go out and get a brand new trials-specific bike. you can do what i did, which is find a smallish mountain bike frame, like a 15" seat tube, that has the right angles (mine is a 15" ross that looks like a DH bike.) and set it up with the right gearing (small in the front). also what i did was i put a 32T chainring on the front so i can ride it around a lot more and not wear out my legs by spinning so fast.
umm...so...i hoped i helped. there are a few other guys on here who ride trials...hopefully they'll pop in here and be able to give you more info.