They were giving away copies of Orphan's Destiny at Dragon*Con in 2005. It was in a stack next to my bed for a while and I eventually read all of it. I'd say it owes a lot more to Starship Troopers than it does Wing Commander, though... so if you haven't read that book or The Forever War, do so immediately.
It's hard for me personally to define things as being 'like Wing Commander', though, since there are so many elements to the series. Does it just need to have similar characters? A similar setting? Also be a World War 2 analog? Etc.
I would reccomend anything in Larry Niven's Known Space universe to Wing Commander fans -- definately the origin of the Kilrathi. The various Man-Kzin Wars spinoff books are the only ones that directly deal with a war, but I'd read something like Ringworld first. The same goes for Jerry Pournelle's CoDominium future history stuff - start with Mote in God's Eye and get into the military stuff if you enjoy it.
David Weber's Honor Harrington books remind me of Wing Commander a lot, in various ways -- probably the characters and the level to which it plays fast and loose with its allegory (it's the age of sail in space instead of World War II.) Start with On Basilisk Station and go right down the series.
The same goes for David Drake's RCN series (Lt. Leary Commanding is the first one, I think), which is pretty much the same concept but done less often by a better writer. If you enjoyed Dr. Forstchen's Wing Commander novels, you would probably like any of Drake's harder military sci fi (Hammer's Slammers, etc.)
