Jody and all .... there are some nice city lakes, but overnight camping is not allowed.
EDIT: I found the link for the Aerospace America show,.. is this the one you are coming to? It's being held at Tinker AFB this year June 9 and that's here in my suburb! You are certainly welcome to come camp at my place! I have 1/2 acre and plenty of room. I'm putting my house up for sale right after I get back from ITG.
http://www.aerospaceokc.com/
This Twin Fountains park is about 8 miles from me, a new RV park and wooded, right near I-44 and I-35, might be a little noisy.
New park nicely wooded