If you can not see the extension then it is either because you havent installed the files in the correct location, or because you havent refreshed the cache.
You should have files or folders titled WebShopApps under
app/etc/modules, and app/code/local or app/code/community. If you do not, you haven’t installed the extension correctly. If you do but you still can’t see the admin options, disable your cache, refresh the front end, log out of admin, login and try again.