domain trading is not dead by any means, but there just are not that many GOOD domains that are unregistered. Like it or not sun-glasses.com will never be worth what sunglasses.com is worth, same with any .net, anything with a number or hyphen, etc. I have picked up a very few good domains I found through
www.deleteddomains.com , but they are few and far between, and though my ROI was better than any other investment I could make with 8 bucks (got 500 for one domain, and 2k usd for another, so it was nice), it just never seemed worth the time to me. If you have a good bankroll (which im guessing you dont or you wouldnt be asking this) you can buy decent domains now and resell them at a markup, but you have to make sure you get a killer deal, and sometimes its hard to put a $ on a domain.