Troy, please contact Great Dane rescue in Texas, they may be able to help you:
Great Dane Rescue Groups
Be aware that your best bet in having your surrendered pet accepted by a rescue is to have him neutered, shots up to date, and a recent heartworm and parasite check. It would be lovely if the dog was microchipped as well.
There are numerous things to consider before surrendering your pet to anyone, rescue or not - please contact one of the posters on this board or ASK what you should be looking for in a rescue. (There's a thread around here somewhere, I just can't find it right now).
I'm sorry, there is no advertising allowed on City Data so I am locking this post, but the direct message feature is still active.