Imbibe magazine's current issue has an article about building a home bar (not the carpentry, or even how to organize it, just what to have). It's in pieces on the web, such as this section on what booze to stock.
It's not a bad article, but I'd question the basic philosophy. I have to agree with someone I read (maybe Ben could help me remember) who said the way to build a bar is pick a basic cocktail, such as martini or margarita, get the ingredients, and then experiment with making it with different recipes until you perfect how you'd like it. I'd go even further, and say that if it's in your means, get a few different brands of the ingredients, and see how different gins or tequilas can be (vodkas less so, at least in mixed drinks, and whiskeys perhaps most of all).
But it did get me to thinking...what are the essentials that you would need to have in order to say you have a respectable home bar? I'm just going to focus on the booze this time, not the equipment or mixers or garnishes. Stripped down to basics, and with an eye for economy (which knocks out, say, Junipero or Old Potrero) what would you need? I'd argue the following:
Brandy Lairds Applejack
Brandy Landy VSOP Cognac
Liqueur Maraska Maraschino
Rum Cruzan (Light)
Rum Myers (Dark)
Tequila Milagro (silver--I don't consider reposado essential, though others might)
Vermouth Noilly Prat (Dry)
Vermouth Vya (Sweet)
Whiskey Jameson (Irish)
Whisky Johnny Walker Black (Scotch)
Whiskey Woodford Reserve (Bourbon)
Whiskey Old Overholt (Rye)
It was tough to leave out some things, especially Campari and cachaça, but choices had to be made...I welcome suggestions, though, and cries of outrage at my choices.