Crooked Can is in Winter Garden and do Growler fills.
They are in a cool building that is more of a co-op than a brewery. The brewers, bartenders & entire staff are great. Below is a link to their website. I would highly recommend going there.
www.crookedcan.com
There is also Orlando Brewing. However, I have not visited this brewery so I cannot comment on if they do Growler fills or not. I have had a few of their beers and they were very good as well.
www.orlandobrewing.com