You need to have an Android powered device (Motorola Droid, Google Nexus One, etc.) with Internet connectivity to buy this product. Follow this link in the Android device web browser (please note, that this link won't work in a desktop web browser). Alternatively, you can manually start the Market application on the Android device and search for "xtralogic rdp". If search for "xtralogic rdp" yields nothing, most likely your device doesn't have access to paid apps on the Android Market.
If your Android device does not have the Google Android market, or does not have access to paid apps, you can buy the Xtralogic Remote Desktop Client on MobiHand.