The breed doesn't necessarily determine whether or not the dog will be calm or do well left alone for large amounts of time.
Just like with anything, breeds of dog are bred to be a certain way, but the individual dog may not be ANYTHING like the breed standard. For instance, collies are bred to herd, but an individual collie may not have a herding disposition, they could actually be terrible at it.
The best thing to do is go to several shelters or reputable breeders and play with the dog several days in a row. A good breeder or shelter should have also evaluated the dogs personality and know whether the dog is calm, hyper, should do well being alone, etc..
One breed of dog that in general is very calm and does well alone is a basset hound. But like I said, just because the breed in general is a certain way doesn't make the individual dog that way. Basset hounds can be hyper even though most of them are calm and sleep a lot.
Collies in general also supposedly do well being left alone for awhile, and as adults are usually pretty calm. Rough collies have long fur but there is also a smooth coat with short fur (though I don't know how easy these are to find).
I have a collie, and in the house he usually just walks around a lot and likes to be petted.
Here's a survey for picking a breed of dog that isn't bad:
http://www.glowdog.com/bestdog/