We just bought a small tree, about 4 1/2 feet, at Fresh and Easy for $14.99. It sits on top of a small table covered with a plush pale blue tree skirt. I only used aqua blue tinsel, birds and glass icicles.
Here is my mantel - usually it just has my collection of white things, but i added some black and white or silvery christmas cards saved from past years. Then i added some mercury glass balls in robin's egg blue and some organza ribbon with blue and silver spots.
Here is the whole effect. Those are twinkly christmas lights on the log in the fire box.