Home depot and lowes both have door skins that come in various thicknesses from 1/16th on up. They are cheap, easy to use and when done you have effectively made your own plywood without any voids.
If you have the patience rip the skins too the width and length you want, glue with TB3 and layer the ripped skins, secure with wood screws as needed and when done you will have produced a homemade version of lvl
I build 18'long sea kayaks and construct my strong-back,2"w by 4"d by 16'L,this way for a perfect warp free surface on which to build the craft.
I will also be building the d/r LB form from KennyM this way.