The downloads are still there, it is just that the links were broken with the domain name change from winampforum.com (which now redirects to forums.winamp.com) to winampenthusiasts.com.
To access the downloads use the below updated URLs.
APK - Winamp for Android 1.4.15
Download here...
http://winampenthusiasts.com/publicd...APKAndroid.zip (Approx 7mb)
Winamp Pro Stub APK
Download here...
http://winampenthusiasts.com/publicd...ub-1.1.0.1.apk
Note: Valid purchase on Google Play/Wallet required