If you don't have a mobile device to test your pages, you can use one of several emulators to simulate a mobile phone, including the following:
Deck-It WML Previewer from PyWeb, available at http://www.PyWeb.com/
WAP 2.0 Phone Simulator from OpenWave, available at http://developer.openwave.com/
R380 WAP Emulator from Symbian, available at http://www.symbian.com/
Nokia Mobile Browser from Nokia, available at http://secure.forum.nokia.com/
SmartPhone Emulator from Yospace, available at http://www.yospace.com/
Using one of these emulators allows you to easily test how well your pages work on a WML-enabled device.
Mobile devices do, of course, include PDAs and phones based on Windows Pocket PC. Although these devices feature a version of Internet Explorer, you still face the problems of a small screen size, so your pages may need to be adjusted and tested accordingly. Find out more about Microsoft Mobile Support at http://www.microsoft.com/windowsmobile/.