Step 1. Go to maps.google.com
Step 2. Find your city and hotel on the map, using first Map to find your country and city, then Satellite to find your street and hotel based on photos from space.
Step 3. Right click with the mouse on the exact location of your hotel, actually even the porch or the entrance can be visible. In the drop down menu, select the item What's here. You will see a green arrow pointing to this location, and numbers will appear in the uppermost input field, right next to the logo of Google maps.
The numbers will look something like 32.327571,-69.229678. These are your Latitude and Longitude accordingly.