No suggestions for you as I don't have any privacy trees, but if you want to grow a zone 6 plant in zone 5 go ahead and try.

Often it doesn't work out, but sometimes it does.

The good news is that if it isn't going to work you will likely find out before the tree gets large and expensive to have removed.

you dont mention how much room to grow is available or if there is a sidewalk. Still, I do have one suggestion.
Unfortunately, I cant lay hands on the receipts for the tree to know the latin name. However, it is a juniper, a blue columnar (but not skinny) type. It looks especially well with the "rose glow" barberry next to one of them. (I have 3) They are slow growing, so if you want instant privacy, go for bigger potted trees. In between the 3 blue junipers, I have one fruitless crabapple, and I keep the branching low, also a "korean spice" virburnum, and one burning bush. This combo covers a strip between me and my nearest neighbor in our front/side yards. Very effective as a screen, enough diversity to be healthy and provides food and shelter for birds. Absolutely no problems with diseases or bugs on any of the above.
Pondy

Thank you for the information, I would love to try them, but haven't really seen any or know anyone who has. Space is not an issue here, I have plenty of it (I know these grow to be quite large), no sidewalk, and only a phone line running along the road, which I can keep well back from. My yard is 3 acres, with most of that being in front of the house.
Thanks!
Angie

We're considering some Black Hills Spruce. They are hardy to zone 3, and are supposed to be fairly fast growers and good screening trees.

HTH!

grullablue- With that much space, go for a mixed planting. Pondy and zone4 mention some good ones, some others are Abies concolor 'Conica', Pinus koraiensis `Silveray'or any number of arborvitae. Stonewall Nursery in Oregon, WI , Yahara Nursery near Stoughton or Reads Creek Nursery in Readstown are good places to look around as well as the Olbrich Gardens in Madison or the Rotary Gardens in Janesville. Now isn't a good time to plant trees, so you might as well poke around and see what you like. If you're adventurous, go to Rich's Foxwillow Pines in Woodstock, Illinois. Most of the places I mention have mature specimens which helps with the "What will it look like in 20 years?" question. Have fun hunting!

tj

Thanks for the info!
No, not planning to plant now... just starting to look around to see what my plan will be when I do plan to plant! =)

No one mentioned the instant hedge of Japanese Lilacs. They can keep your visual block intact until your desired hedge is grown.
Plant this summer and they should be tall enough and thick enough to do the trick next year. Lots of water though, and when it is time to get rid of them - prepare for chemical warfare or lots of digging.

try this site to see a blue juniper.

Here is a link that might be useful: rabbit run nursery