I won't be able to call in so I'll post.
I use sites I hear about from word of mouth mostly, I won't just up and use any site. If multiple people have tried it and found it to be legitimate, I'll give it a shot.
Here's the online sites I've tried.
Wine Woot: Interesting and quirky wine site that sells one wine per week starting at the 0:00 hour Monday morning [midnight Sunday]. Their selections usually hail from California, with the occasional Washington and Oregon mixed. They have offered Sake, Sparlking Wines, and fruity summer quaffers. They choose the wines by hand and are sure to taste them first, and the prices are low so you usually get a deal. Customer Service is top notch and they will give you offers on free shipping for problems, and will replace broken or bad bottles no questions asked. On the downside, you are usually purchasing a "bundle" meaning you get anywhere from 2-6 wines depending on that weeks offering which can be 3 of the same wines or a sampling of 4 different vintages/varietals. You can only buy up to 3 of the bundles. Online community forums are strong, and the winemakers often post and answer questions. Shipping is a flat $5 no matter how little or great your order. Gotten a couple great offerings, one not so much. Also if you live in Jersey, Mass., Arizona, and a couple other states, you can bank on LONG delivery times due to horrible state regulations [if you can even get the wine to begin with]. It took over 2 months for my Kunde wine to get to me... I can get a car made and shipped from Europe in less time.
Wine Library: Many are familiar with this site. Huge selection, wonderful online community. free.winelibrary.com offers a daily selection with free shipping starting at 1 PM. Shipping is fast, in Jersey it got to me overnight.
WinesTilSoldOut: Offers one wine per day at seemingly rock bottom prices. Site has it's quirks, offering different vintages from the picture and sometimes wines that could be past their prime, like one I just got, so you get what you pay for. First bottle was eh, 2nd was much better and worth the $13 per bottle. Free shipping if you buy a minimum amount of bottles. Takes few days for the order to get process, from 3-5 days.
Garden State Wine Club: Not truly an online site as you can't buy online, but you can sign up for the club online so I feel it counts. Unlike other clubs, you can mix and match reds, whites AND price points, I get 2 $10 reds, 1 $10 white, and 1 $20 red per month. Club is priced according to dollar value and is not a flat rate, so you won't get screwed by a club that charges you $20/month and sends you $15 worth of wines. Competitive prices, reorders of monthly offerings can be had for great prices. Shipping is free, but your order will come once a month with your club offering. Very pleased with the offerings I've received so far, no complaints. They do not offer any sort of a catalogue other than an online list of previous monthly offerings, which is annoying because you don't really know what they have in stock and what you can order.