i personally wouldnt buy it alone, but it is in a lot of products, i have enver taken it alone so i dont know about any results, i know that you can get it in your protein shake mix at proteinfactory.com, in the protein lab.
I've taken it alone and noticed that I tightened up slightly. Nothing worth bragging about though. I made sure that my diet remained consistent so I could test the product on its own.
I could see how it might be useful if you're looking to tighten up for a show or something, but you'll get the same results if you just drop your cals slightly for a week.
fish oil is a must for your omega 3's, CLA is useless. I take fish oil pills everyday with my vit and mins., tried CLA for 3 straight months....no obvious inherent benefits.