The LifeDrive is discontinued and that's why you can't find it in stores. A few online retailers still have stock though.

In the Windows Mobile camp, the HP iPAQ 110 (QVGA 240 x 320 pixel display) and the iPAQ 210 (VGA display) are worth a look.

http://www.mobiletechreview.com/HP-iPAQ-110.htm

http://www.mobiletechreview.com/HP-iPAQ-210.htm