Magento Auto Address Finder is an extension that allows your customers to auto complete their address from the partial address they have entered or are entering .
On checkout page, when customer enter billing or shipping address then on address field will suggest addresses when cursor on this field, and also when customer enter their addresses from dashboard -> add address page then also same address filed will auto find address on selected country.
1 . Upload file manually – Extract it and then extract Custom_Addressfinder-1.0.0.tgz and then copy all files app and js folder and then paste into your magento root directory, If you are using a different theme from default theme – be sure to copy app/design/frontend/default/default/layout/addressfinder.xml to your theme layout folder app/design/frontend/yourtheme/yourtheme/layout/addressfinder.xml and copy app/design/frontend/default/default/template/addressfinder to your theme template folder app/design/frontend/yourtheme/yourtheme/template/addressfinder.
2. Second way is from admin panel – Go to admin panel – System -> Configuration -> Magento Connect -> Magento Connect Manager and unchecked ” Put store on the maintenance mode while installing/upgrading/backup creation” option and browse file and upload it.
3. Clear Cache
4. Now goto checkout page, when you enter address then it will auto suggest address based on your country.