Google can be a huge help in finding APK files to install on your Android device. This is a must if you’ve accidentally deleted an application that you can’t find in the Market or if your device cannot access the Market at all. You can find free games, apps, widgets, live wallpapers, etc.
Since some people (lots and lots) leave APK files in unprotected directories, you can use Google to search these and dig up the treasures.
A general search for APK’s: -inurl:htm -inurl:html intitle:”index of” apk
To look for games: -inurl:htm -inurl:html intitle:”index of” apk games
To look for a specific type of game: -inurl:htm -inurl:html intitle:”index of” apk solitaire
You can also use Google to search popular file storage sites like Mediafire to locate stored APK files.
A general search for APK’s: site:mediafire.com apk
A search for Live Wallpapers: site:mediafire.com apk live wallpaper
XDA Developers do a lot of modified and customized apps, to search there: site:xda-developers.com apk download