Hiya Bob,
Yes there are a few good schools out in the USA. I'm not sure if you can do the PPL at Tyler through Oxford or not. I can strongly recommend a school in Tulsa Oklahoma though as in my opinion they are fantastic. Excellent instruction and they also look after you really well while you are there.
I'm out here doing the Multi IR with them at the moment and can't find a bad thing to say about them. There are three other Brits out here who are doign their PPL's and they are all loving it as much as I am. Much better than some of the horror stories you hear about some other places (one of which I found out the hard way).
If you want more details let me know.