OK...first off, an SLR camera is little better than a regular point & shoot camera if you don't know how to use it. So plan to do some research and learning...it won't be too hard and it's lot of fun.
You could think about getting a used camera. If you go this route I'd suggest going to a camera shop.
Usually the EOS rebels come with something like a 28-90 lens. Usually the cheapest lenses. It would be an all around OK lens but maybe not the best for you. The 75-300 is an OK lens as well. It's a little slow (you can learn what slow means later) but you will probably need at least 300mm for shooting football. Don't be afraid to get a Tamron or Sigma lens to put on a Canon camera, they are good lenses at good prices.
It's almost always helpful to have a nice sharp fast lens. This means you can get better shots in lower light situations without resorting to undesirable on-camera flash. The Canon 50mm F1.8 is one of the best investments and it's the cheapest Canon lens.
If you can afford it, I'd suggest you get two lenses...the 50mm F1.8 (it's a prime lens which means no zoom) and a zoom. The 75-300 or something similar.
If you can't afford another lens with the camera...a standard lens (like the 28-90) should be OK for the trip to Alaska. You will probably need to get some scenery and people shots. This lens might not be the best for shooting football but you can alway get a better lens when the time comes.
Go down to your local camera shop and hold a few different cameras and try out some of the lenses. This will give you a better idea of what you are getting into.
Also...start reading up on basic exposure. Once you learn about aperture, shutter speed, depth of field etc. you will be on your way.