Try Rock Crusher Canyon in Crystal River, Florida. ?We recently stayed there...over 700 campsites, but you'd never know it...downhome, friendly hospitality. ?We paid something like $25 per night (and that was just a short term stay). ?They have a great Club House with a big screen TV, hot tub, pool and their bathroom facilities actually offer an entire full bathroom PER PERSON (sink, toilet, and shower)...no sharing space when going to the bath house. ?They also have an outside Ampitheatre and have an occassional concert (Gretchen Wilson is playing there early November) It's just beautiful. ?I'm sorry I don't have the link to their website, but I'm sure you can find them on the web.
The Great Outdoors (TGO) in Titusville is great but does not meet your "inexpensive" criteria. However, for long term stays, you can usually get better rates from individuals renting their lots. I have attached links to TGO's website and the latest edition of the classified section of our community "newsletter" listing some individual rentals.