If using the free emulator (http://blog.brightpointuk.co.uk/emulate) isn't providing you with the Android experience you are looking for, the operating system is now available as a LiveCD ISO image. This means that you can download the ISO image and use it to burn a bootable CD, then boot your laptop or desktop from it and run Android on your own PC.
NOTE, at this stage only X86 platforms are supported rather than 64-bit machines.

Alternatively, you can use the ISO file to run a virtual machine using VMware or Sun VirtualBox.

The ISO image can be downloaded from the Google Code web site - http://code.google.com/p/live-android/downloads/list

The ISO image will come down as 2 'split' files. Windows should be able to re-join these files automatically. On a Mac, you will need to use a free utility such as the excellent 'Split & Concat' tool:

You can then use your virtualisation application to create a new virtual machine, selecting the option to use the ISO file as the machine's CD drive:

Enjoy!