You can rig up a dehydrator fairly simply if you want to try your hand at making one.....Mother Earth News has plans for several in their online archives, as well as other places on the internet.
OR
set your sliced food in your oven, on cookie sheets or small grilling racks, at about 125 degrees, remember to turn every few hours. If you have slices of 1/4 inch or less thickness, they should dry in 12 - 24 hours. I made jerky this way for over 15 years.
Another way is to take a small box fan, set it at lowest speed, lay your sliced stuff in the air flow, cover with cheesecloth if you want, turn it often, and let it dry. If you can, raise it above the counter level so air can get beneath it as well as over the top.
Doesn't heat up the house as much as the oven, but doesn't work well for jerky, or other meats.
Some veggies can be "strung up" - run a doubled piece of white sewing thread thru one end, (like making popcorn garlands for a xmas tree), and hang up where it can get a strong breeze. They used to rig a drying line in kitchens up near the ceiling from the chimney across to a rafter beam, and hang onions, garlic, "leatherbritches" (beans in the pods), and herbs and flowers to preserve for winter. My grandmother even had one in her kitchen in California until she passed in the early 70's. Works real good for peas in the pod, greenbeans, pumpkin chunks, carrots, etc.
Kathy
P.S. - I've got recipes for fruit leathers if you're interested. I've heard they can be used with tomatoe pulp as well.