Here are three sites to enjoy while thinking of making cocktails. Of course there are others. This is three.
First, About Cocktails. Don't you just love About.com sites? The best ones from ages ago are still really good. People have invested a lot of time and effort into them. Colleen Graham writes this one, and I enjoy keeping up with her additions. Here's a direct link to martinis and other classic cocktails you should know how to prepare.
Second, good old time cocktails at the kitchn to impress others with, plus if you look around the site, lots more to appreciate. The Aviation, my favorite cocktail, is listed here.
Finally, Difford's Guide. To pretty much everything you'd want to know, contemporary cocktail-wise. And some of it is video, which I know a lot of people who aren't me do enjoy.