Major question: What to do with "The Floor"?

After careful perusal of this site, I'm totally convinced that floating my floor is a BAD idea. Which leads to the rather obvious question: So then what DO I do with my floor? How should I build it? I've been searching this site for the last couple of days, looking for answers, and I haven't found very much to go on. And since my eagerly-awaited copy of Rod's books still has not arrived from Amazon, I'm in the dark as to what I should do. The concrete slab that I have to work with is not very even, slopes slightly, has dips and high spots, is stained with oil in places (it's a garage), is chipped, gouged, ugly and in general is unsuitable for use as the direct floor. So what should I put on top of it? How do I level it? How should I seal it / treat it? what can I do to improve isolation and reduce flanking? Any suggestions? Links to stuff I missed here? What are other people doing who are NOT floating their floors? Help! Stuart.

Make it look nice. I'm serious. My first thougt is self leveling concrete to, well, level it, then stain/etching. Andre

Thanks, Andre. That might work. Do you think an inch or so would be enough? Two inches? I don't want to go any deeper than I have to, since I'm already tight on headroom. Also, there is a "slight" problem: There is a sewer inspection chamber in the floor, which I cannot get rid of. I'd basically have to rip up half the house to move that. Not an option. So I need to work around it somehow. It has to be accessible, although it could be covered as long as the cover is removable. It's in the live room, fortunately(?), not the control room. As an alternative: I recall reading somewhere (maybe not here) that one option is to put down a thin layer of dry sand to level the floor, then a layer or two of plywood, and "laminate" floor on top of that. I think you call it "laminate" in the USA? Here it is called "floating floor", but of course isn't really floating at all. Just basically tongue-and-groove MDF engineered to look like various kinds of wood. Is that an option? Good idea? Bad idea? Also, if I went with your idea of pouring an extra layer of concrete, should I plan to put my "inner leaf" walls on top of that new concrete, or just build them on the old concrete and only pour the floor inside of that? Would that have any acoustic advantages / disadvantages? So many questions....! I really wish Amazon would hurry up those carrier pigeons and pack mules with my copy of Rod's book... they seem to have gotten lost in the mountains somewhere.