Tracy, as you can tell from my username, I play whistle. It's relatively easy. I also play fife, and I think whistle is the easier of the two. Some hints, don't spend too much on a whistle, but definitely shop around for a good whistle. Quality and playability varies, even among the same manufacturer. A good video tutor is "Learn to Play Irish Tinwhistle" by L.E. McCullough. Another good resource is the book "Traditional Irish Tin Whistle Tutor" by Geraldine Cotter.
Also, I'm a part of an online Christian whistle community called Praise Whistlers. You can check us out at
http://www.format.com/cgi-bin/yabb/YaBB.cgi?board=PWAD
There's also a good whistle site at
www.chiffandfipple.com where you can find out anything about whistles, and read the message board there.
I heartily recommend going to the Praise Whistlers board and reading and asking questions there. It's a very friendly board, the chiffandfipple board usually is friendly but can get a little rough now and then. If you go to the PW board, I'm known as papawhistler there.
Best to you.
Scott