I put in a few ninebark 'diablo' shrubs for similar reasons. They're deciduous, but I don't really care about privacy in the winter. They're very hardy, fast-growing, shade tolerant, and look really cool. Depending on how tall and bushy I want them to get, I have the option of either gently pruning them or cutting back to the ground each year. Max height is 5-8 feet.

It's your lucky day! There is a great site for landscape plants for Wisconsin. The link is below. You might want to read up on Sambucus canadensis laciniata (a.k.a. acutiloba). I'm considering it for a situation similar to yours.

Rhoda

Here is a link that might be useful: Midwest Landscape Plants - Lots of Plants for WI

you may want to look into some of the holly bushes (Ilex sp) for your hedge.

they can be evergreen and are more appealing to me than the often used cedar or pine type shrubs. many of the hollys have sharp hard pointy leaves that hurt if you rub against them. i am not sure how fast they grow but i think they do fill in nicely.

Here is a link that might be useful: info i found about Ilex meserve

rogusa roses would help with the neighbors-- they make
a nice hedge, but are kind of low (4 feet). lilacs would give you some height behind the roses and are oretty fast growers. You could also try for a beech hedge-- they hold their leaves most of the winter.
diggerb

Broadleaf evergreens (holly) are tough to grow in Wi unless they can be sheltered. Even if they survive, the "green" leaves look beat up by late winter. Ninebark Diablo has purple foliage, might be a bit much for a hedge. Beech is nice but I think the growth rate is relatively slow. Rugosas or landscape roses would be nice, Lilacs would work. Junipers can take an exposed site. Viburnums come in multiple varieties & have scent, flower & berries (no thorns tho). Arborvitae are deer magnets so they may not be the best choice if deer are a problem. The above suggestions are based only on my experience. Your milage may vary.

Holly and golden Forsythia are good hedges..Holly takes longer to grow..I have to cut back my golden forsythia several times in summer or else it'll turn into trees..lol..Toni

If you want something thats green year around and dense please try some of the great arborvitae they have now. The birds will love you and there are some great varieties. We just planted a hedge at my daughters in the twin cities last fall.

Shirley

Be carefull with your arborvitae selection. Some varies get severly burned by winter winds. There are some varieties that would work very good though. It is an instant solid wall if you plant them close together. They are not that big around so they dont take up alot of room either.

Was just looking at my notes on landscaping our daughters home and thought I'd share this info with you. Techny Arborvitae (Thuja occidentalis 'Techny') is what we used. Its for zones 3 to 8 and maintains a dark green color all through winter. You can keep it trimmed to 6 foot or if you let it go it could grow to be 15 feet. Good luck with whatever you decide.

Shirley