You could build this beautiful antiqued panel mirror, perfect for your entryway, using the free tutorial at the link. there are even instructions on how to antique the mirror.
This mirror was made using eight 12 x 12 inch square mirrors bringing the cost way down. Here is how to build the frame.
Frame an inexpensive floor length mirror using this free tutorial. Easy.
To build a mirror frame you will need to pick up some corner blocks and fluted casing, a pre-cut mirror, and some sturdy mounting materials from the aisles of a home center.
Build this Asian-inspired design with wedged tenons. Free plans to build a wooden mirror frame are provided at the link.