Erin McGrath has a cool post up on Palate Press with some great wine bar guidelines. Erin has her own blog called Vintwined that focuses on some California wines. As someone who is still pretty new to the wine world, I can definitely remember struggling with some of the confusion that she mentions in trying to describe what I like to someone when ordering wine.

One big faux-pas that many customers commit is misusing descriptors when communicating the types of wine they prefer. Here’s a quick low-down on three commonly butchered terms:
Dry. As in: “I usually like red wine, but nothing too dry [grimaces while holding throat].” Of course I understand what this person means, but I almost always ask follow-up questions, not only to make sure, but also to help him/her understand the word “dry” when it comes to wine. “Dry” means a lack of sweetness—not that mouth-puckering, cotton-tongue feeling. “Tannic” is the word you’re looking for, as in ”I usually like red wine, but nothing too tannic.” Bingo, grasshopper—now I know what to suggest.
Sweet. Unless you’re talking about a dessert or late-harvest wine, a port—or, heck, Riunite—you’re likely misusing the term “sweet” as a descriptive word for fruity. A fruity wine is often mistaken for sweet due to its fruit-forwardness or, in the case of many Zinfandels or Shirazes, a “jammy” quality. When a customer requests a “sweet” red wine, I clarify and ask them what types of red wines they drink. More often than not, it’s Zinfandel, or younger California Cabernet.
Crisp/Acidic. Ah, my favorite: “How about a bright, crisp Sauvignon Blanc! But not acidic.” What? ”Crisp” denotes an evident level of acidity in a wine, so fulfilling this customer’s request is nearly impossible from the get-go. There are certainly white wines that are too acidic, mostly because they’re poorly balanced or really cheap plonk. Bearing that in mind, however, a well-made Sauvignon Blanc will have some acidity, making it “crisp” (or tart or tangy or refreshing or another acidity-denoting term). If some wines give you acid reflux, I’d suggest switching to a softer style of white, maybe a Viognier or Chenin Blanc. Or put an ice cube in it. If you must.

Where I live there is really only one wine bar that I am aware of. There might be more, but I have never been to any of them. La Diosa Wine Cellars is owned by the same people who own McPherson Cellars Winery, one of the better West Texas wineries. The atmosphere is really great there, and they have a decent selection of wines, although they are mainly regional wines. I have mixed feelings about this, since I am all about buying local. 
I think that it is really important for a good wine bar to have staff who know to ask these kinds of questions to help newbie wine drinkers select wines. I can remember being very overwhelmed and frustrated trying to pick a wine, and I seldom really felt like the staff at restaurants and wine bars were very helpful in helping me out. I received some truly puzzling recommendations, and in hindsight I think this was due to me not communicating what I liked properly, and the staff not asking the right questions to point me in the right direction. With a little help I probably would have gotten into wine earlier, and that would have been good for me and for my local wine bar.