In Terminal execute below to get your MD5 fingerprint:
~ uki$ keytool -list -alias androiddebugkey -keystore ~/.android/debug.keystore -storepass android -keypass androidandroiddebugkey, Jun 29, 2011, PrivateKeyEntry,
Certificate fingerprint (MD5): 65:4D:21:AA...
Go to the site:
http://code.google.com/android/maps-api-signup.html
Copy the fingerprint: 65:4D:21:AA...
Your key is:
0wbj...
This key is good for all apps signed with your certificate whose fingerprint is:
65:4D:21:AA...
Here is an example xml layout to get you started on your way to mapping glory:
<com.google.android.maps.MapView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:apiKey="0wbj..."
/>