Alright, 2 racks of pork back ribs, but no smoker or charcoal grill. How should I cook them?

What do you have available?
If you have a gas grill, you can make it be a smoker. Either hit the Lowes/Home Depot and in the grill section they'll have a "smoker box" which you can fill with wood chips, or you can just wrap them up in aluminum foil. Use only one burner to keep the temps down, put the smoker box/foil above that burner, and cook ribs at 225-250 degrees until done. (Tons of ways to do it--I personally season them, run them three hours in the smoker, wrap in foil for 1.5 hours, then unfoil and sauce for last 30 minutes.) Key point--the smoke should NEVER be billowing out in thick white smoke. If so, it's going to make it taste like crap. You want thin blue smoke, almost so thin you can't see it.
If you don't have that, you can always just use your oven. Put them on a baking sheet (you may want to put a wire rack in the sheet to get them off the bottom because a lot of fat will drip off), and cook the same method that I described for the gas grill. The only thing you'll be missing in smoke flavor. You can add liquid smoke to the seasoning to avoid that, but I think it's unnecessary.
Obv there are slow cooker recipes like 320 offered, I could tell you how to do it sous vide but I assume that's "insider bullshit"... Heck, I could give you an awesome recipe for Hunan-style cumin pork ribs if you have a wok. But the above should get you started.