Google has a pretty clumsy URL for searching with SSL, like Wikipedia. However, the encrypted version of Google Search is currently only in beta, so it may be the reason behind it. Anyway, here is the URL to it:
To change to your country’s version, replace the last two letters en to something more fitting. In my case sv since I’m from Sweden.
With the Firefox add-on Add to Search Bar you should be able to add an entry for this version to your search bar. And as with all other search fields in Firefox, it’s possible to add a keyword for the search field by right clicking the field and pressing “Add a Keyword for this Search…”.
However, if you care about your privacy, don’t forget to check out DuckDuckGo. Click here to read my short introduction to the search engine.