My friend Jeff points out that I've given equal time to wine and beer, but liquor, or liqueur if you prefer, has been given short shrift on this blog.
This post aims to even things up a bit.
There are really only two things you need to know about hard liquor.
One: Don't have a martini bar at a Sunday party, especially if your guests are used to beer and wine.
And two: If you no nothing else of drink making, learn how to make sours.
What's a sour? It's pretty self-explanatory. It's adding some kind of sour liquid, usually lemon juice, to hard liquor. Usually some sugar is also added to balance things out. Shake with ice, strain, and serve.
Fresh lemon juice is best for a sour. (What, you were expecting me to say using bottled juice is OK here? Well, you do what you feel is best.)
Instead of sugar, which can be gritty even after you've shaken it silly, you could also use a simple syrup, a mix of sugar and water heated until the sugar just dissolves. But sugar works fine, especially if you're not straining the dregs of the drink into the glass.
My advice for ratios is to make a couple sours, and find what ratio you like best. A good start is a half a lemon, and 1-2 tablespoons of sugar for each ounce of liquor.
Just make sure you taste the drink, and adjust if needed.
If you really must have a recipe, here's one that's good for an individual serving, and here's one from Ina Garten that's enough for a crowd.
Have fun, kids!