The valuable and informative Transom website has a comparative portable digital recorder review which lists most of the more available and popular brands here.
The recorder of choice used by the photographers attending my Multimedia Storytelling class at the Foundry Photojournalism Workshop (Mexico City) was the Zoom H2, an easy-to-use and inexpensive model. The feedback I got was that it performs well...but that its controls are not really intuitive, and that it feels somewhat fragile,
I'm still using the M-Audio Microtrack that hasn't performed as it should have in the past few weeks. I'm not sure whether its a software problem, or whether it decided it had reached the end of its useful life (it hasn't been used long enough for that).