Is there something wrong with the one that came with the camera? There are lots of different straps out there depending on what you want, and how much you want to spend. I have always used the strap that came with the camera until a few months ago. I got a neoprene strap free from Smug Mug and I really like it. Pretty much the same design as the the original Canon strap, but much more comfortable.
Right now none of my cameras even have straps on them because I have been doing a lot of work from a tripod and the straps kept getting in the way.
"I thought that because fewer wolves meant more deer, that no wolves would mean hunters' paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view."
Aldo Leopold
I prefer the straps with the buckles so you can remove them. Often times I don't want one on and it just gets in the way. Its hard to find one with the buckles that isn't monstrously huge though.