A coworker recently showed me the Google Doodle archive where you can see all of the past doodles (including those featured in other countries). It can also be a good resource if you are trying to locate the artist that created a particular doodle (as I often am!). I'd say they're credited about 50% of the time.
Here are a few of my favourites that have graced their homepage lately:
Interactive Hallowe'en doodle