Buying organic/free-range/grass-fed meat online

The best option would be to find someplace local.

Try here for a start

http://www.florida-agriculture.com/consumers/farmers_markets.htm

Not sure how close any of those are to you.  If there are any close you can talk to the farmer there and see about bulk orders.  For farmers getting money up front is always awesome, so they'll probably be happy to help you out.

Here's a list of Florida CSA's

http://www.florida-agriculture.com/consumers/community_supported_agriculture.htm

Quite a few of the CSA's around here do deliver or are open for visitors to come buy products.

It's amazing around here in the DC area how many options we have now.

We have multiple sources for milk, meat, produce, etc deliveries all of local sustainable, some organic, etc farms.  We get probably 75% of our groceries delivered from local farms.

My wife probably has more resources, I'll ask when I get home.

I googled "pastured beef and chicken florida" and came up with several farms- not sure if any are close to you (Cognito Farms, and Pastured Waygu were two).  "Pastured" is a typical term for the methods of maintaining a grass fed beef production, and it often includes chicken raising as well.

Ask around- we found our current beef supplier through friends- she raises about 10 head on a small farm, and we purchased a half from her.  Also check out the Amish in Florida (one link: http://www.millersorganicfarm.com/)- we have a large Amish population here, and we found a family that raises chickens and hogs, and we got a half hog from them (yummy bacon!).  All very reasonably priced (but we are in Upstate NY- in Florida YMMV).

Good luck!