Mully, if the Prilosec OTC didn't work for you, don't bother with the omeprazole..... they are the same thing.
Jack, I'm surprised that quitting the cigarettes didn't improve the problem for you. I, too, went through all of the prescription medications, including Axid, Prilosec, Tagamet, Pepcid and others. The only things that would help were Nexium and Prevacid. Once I lost my insurance, my options dried up. Prilosec (omeprazole) twice daily or OTC Prevacid help but aren't really affordable to me right now. One thing you can do that really does help is elevate the head of your bed or sleep with a wedge. The problem (and the resultant damage) is usually worse at night due to gravity. When you're reclining, the acid makes its way up from your stomach. Elevating the head of the bed helps "keep it down". It looks silly as Hell but is effective. Also, avoid eating before you go to bed and stay the Hell away from anything fried!
Something to remember, stomach acid is hydrochloric acid. It is an industrial corrosive. The stomach has mucus and a protective lining that protect it from acidic destruction but your esophagus doesn't. You really should have it checked (if your doctor recommends) by endoscopy, under sedation if necessary.
Seriously, try putting blocks under the bedposts and see if it helps.