japanese maple comes to mind. check out the JM forum here at GW.

You can also consider a large shrub, many of which can be pruned up like a small tree.

If there is a regional gardening book, check there for shade trees/shrubs. Check out the Brooklyn Botanic Garden website to see if they have a listing. If the NY Native Plant Society has a website, check there. Go to a local public garden or arboretum - ask the staff, look around. Contact your local county extension agent - his/her office may have a list.

The JM forum is listed as "Maple Forum", even though it's almost entirely about JMs.

At 10' you're looking for a large shrub. Gray Dogwood (Cornus racemosa) can be purchased in tree form and is quite tolerant of soil and shade conditions. Another large shrub that makes a dandy little tree is Viburnum prunifolium, but it won't handle full shade conditions. And for something way outside the box you could try Leatherwood (Dirca palustris), which is a shade loving shrub that has a natural tree form.

Bob

Forgot to mention this Gray Dogwood selection, which seems to meet your size needs if nothing else.

'Ottzam' (OttawaÂ) - A fastigiate tree form growing narrow to 12' tall and 6' wide. Perhaps useful under power lines or in moist situations.

How much shade are you talking about? Shade has gradations, ranging from NO sun, such as between tall buildings, to under dense trees, to dappled shade, to morning sun/afternoon shade. All come under "shade", and most plants can cope with the last 2. The first one is difficult; it is very hard to find plants that can cope with it, and the second has a few more plants that will grow in that level of light.