When my wife and I created our community garden we installed birdfeeders (sunflower and thistle) and birdhouses to support the birds that nest in our area. I built the bird houses from a single length of 1x6 cedar from Home Depot using these simple plans. Just 5 cuts with a Japanese handsaw, a few finishing nails and they were ready for mounting. Birds moved in within hours. Here's a photo of a cedar bluebird birdhouse, ready to be installed.
Here's another great site with house blueprints for several bird species.
My next project is a tree-mounted house for
Black-capped Chickadees
Carolina Chickadees
Mountain Chickadees
Chestnut-backed Chickadees
Boreal Chickadees
Siberian Chickadees
House Wrens
Carolina Wrens
Bewick's Wrens
Winter Wrens
Prothonotary Warblers
Tree Swallows
Violet-green Swallows
Tufted Titmouse
Plain Titmouse
White-breasted Nuthatch
Red-breasted Nuthatch
Brown-headed Nuthatch
Pygmy Nuthatch
Brown Creeper
I highly recommend building cedar birdhouses with hand tools. It's great therapy.