gored: There have been at least two other threads on STL jobs in the recent past. Try a search.
That said, what I'm aware of, briefly:
FLX at CPS, my alma mater.
CASW at CPS, another 135 freight op
Airnet has a couple (maybe more?) CPS runs, but they don't to my knowledge hire in to base.
If you're a CFI and you can bear the thought of instructing again, Parks College was hiring not long ago. Also there's St. Charles Flying Service out to the northwest...instructing, plus maybe some 210/310 135 charter work.
There's always pounding the pavement at SUS for that "right place right time" corporate gig.
I'm pretty sure JetDirect or whatever they're calling themselves this week are not hiring for STL.
Avantair, Citationshares, Netjets (yeah right), etc all seem to have STL domiciles.
Again, check for those other threads, I'm pretty sure some other guys contributed some good ideas.