We recently bought 3 banana trees and they are now getting brown spots all over them, we first thought it was tranaplanting shock, but the new leaves being produced are also getting the spots. Can someone tell me what the spots are and how to treat.

Banana plants (Musa paradisiaca sapientum) are tropical plants that make good houseplants in our area. They need a nice bright location indoors and regular attention to watering and fertilizer.
Bananas also make nice additions to a summer garden outdoors. Banana plants require lots of water and fertilizer to reach their full potential. They prefer a rich, loamy soil to support their roots (actually rhizomes).
Bananas that are planted in our summer gardens will not survive our winter temperatures, so care must be taken to preserve them for replanting in following summers.
Because of the tropical nature of bananas, they need to be protected from freezing temperatures. Use a digging fork to lift the roots out of the ground anytime before the first hard freeze. Bananas will tolerate light frost, but a hard freeze will damage the root system. These plants are shallow rooted, so they should be relatively easy to get up.
Shake off the soil and let the roots dry out on newspaper for a couple of days in a protected area like the garage. You can then store the roots in a box with vermiculite or in potato sacks. If your banana is quite large, you can pot it up in a large pot and lay it on its side. These plants will do best if stored in a cool, dark room. An ideal spot would be a basement storage room or closet.
You can replant your banana late May when the soil warms up.
Bananas are susceptible to a number of insect and disease problems. Black leaf streak, anthracnose are leaf diseases caused by fungi. Mosaic and wilt diseases can also be a problem. Occasionally aphids, spider mites and mealybugs can infest plants. None of these issues tend to be debilitating, just keep the plants as stress free as possible and remember that they like lots of water. Water the soil around the plant though, not the leaves if you are seeing leaf spots.

If your plants really look bad, take a leaf sample to the Extension office have them take a look.