I am about to install some 3/4 Oak on my main floor. In my hallway I have an 8" x 24" air return in the floor. Looking around on the web it seems that a wood grill isn't the best thing for a high traffic area. Regardless of that I still am having a hard time finding a grille of any sort that isnt priced at $800.

What do the pros usually do with a return that size in the floor?

That big, Steel!

I wouldn't want my foot and leg going through that, or my kid running down the hall, doing the same thing.

http://www.classicvents.com/flushf2.htm

These are solid grilles.

I generally use an "egg-crate" style vent with these larger holes, and if in a walking area where there is a danger of being stepped on, I bolt a piece of angle iron between the joists underneath to stiffen the vent up and prevent breakage. If painted out to approximately same colour as the floor, it is virtually indetectable when looking through the vent

Well there is a a joist in the middle of the opening since the duct uses two joist bays for the return. That should help with support.

This makes it pretty reasonable to use a wood grate now.

Those vents from classicvents.com are what I like, hope they are not to expensive.

Now if I use a flush to frame vent I don't think I will have to many tongues fitting in the frame because of layout. Does that really matter or should I go with a self rimming vent?

Thanks!

The flush mount vents are much more attractive in a hallway area and do not present a trip hazard. I ALWAYS rout a groove into the bordering floor boards and spline and glue the frame securely into the floor