I found a great site for just that thing!  Eatwild is a great resource to figure out where to find grass-fed/pastured products in your area, and to learn about all the benefits.  I choose to eat grass-fed only products because I believe a natural diet for the animals can only result in healthier food for us.  Not to mention that we are putting back into the earth what we take out when animals are pastured.  Oh yeah, and it tastes better.  Pastured animals don't need antibiotics because they are eating a natural diet.  Which means we don't get pumped full of unnatural crap either.  Buying meat in bulk can be kind of tricky, but I have found that the farms are incredibly helpful.  There are also buying clubs where you can link up with other people in your area to create a pick up location for us urbanites that may find it harder to get to the farm locations for pick ups.  Check out the site, it's great!