The onset of the holiday shopping season is as inevitable as death and taxes. However, unlike death and taxes, the stress associated with shopping can be minimized with a few nifty shopping hacks. You just have to understand the marketing and pricing strategies employed by most online retailers.

Commercial retailers didn't really get the hang of online commerce until the late 1990s. But they've since caught their stride, amassing huge databases of information about customer behavior. They use this information to tune their pricing, special offers and promotions accordingly – for instance, offering online promotions midweek, so consumers can shop at work. The flip side: Savvy customers can take advantage of merchants' strategies to score great deals.

With about six weeks left until the December solstice, Christmas and Kwanzaa, and 25 days to the first night of Hanukkah, here's a collection of shopping tips to help you find the best deals online.

Start shopping early. Thomas Harpointner, the CEO of e-commerce consultancy AIS Media believes that it's better to start sizing up gift options and online retailers as soon as possible. "The end of back-to-school really represents the beginning of the online shopping season," says Harpointner. "Once Labor Day ends, online retailers know that there isn't much on the calendar except Thanksgiving, so if consumers aren't already looking around they may actually end up behind."

Sign up for newsletters. According to Harpointner, one of the best ways to score early deals is by signing up for e-mail newsletters from retailers. "Online merchants understand that people are spontaneous," Harpointner explains. "So if customers receive an e-mail with an offer or coupon that matches their shopping list, there's a good chance they'll make the purchase early."

Use coupon codes. In addition to e-mail blasts, cost-conscious online shoppers can also augment their savings with coupon codes, which they enter during the checkout process at specific merchants to get a discount. Most merchants offer codes for free shipping, but with enough searching (try entering the words "coupon code" plus the name of a product or merchant on any search engine) diligent shoppers can drum up codes for merchandise discounts and even free accessories. Or check a coupon code site: Currentcodes and RetailMeNot are two of the larger hubs on the web for sniffing out these codes.

"Coupon codes really are one of the internet's hidden treasures," Harpointner admits gleefully. "Everyone uses shopping engines like Buy.com, but what most people don't do is a separate search for coupon codes. Flowers.com is famous for (offering coupon codes). It's helpful and gives customers an additional incentive to shop online and beat the mall traffic."

Get the jump on Black Friday. Not everyone is organized enough to compile lists and sift through promotional e-mails week after week. And let's face it, some of us will always be doing our shopping at the last minute. If that's your style, there's a whole separate set of online shopping tricks and a totally different timetable.

The key to this method is to tackle the day after Thanksgiving head-on. This date, which is known as "Black Friday" in the retail trade (and which falls this year on Nov. 23, the earliest possible date), is one of the busiest shopping days of the year. Many merchants offer special deals, online and offline, to help goose weekend sales even further. The trick is getting advance information on the planned discounts, so you know where to shop and when.

Sites such as BFAds.net and TheBlackFriday.com provide details on major retailers' Black Friday sales plans. While retailers such as Wal-Mart have sought to shut down these sites, much information is still available. If you spot something you want listed in one of these contraband ads, you can easily outflank other shoppers by hitting the retailer's website early – say at 11:59 p.m. EST on Thanksgiving day.

Shop at work. If Black Friday doesn't produce the killer buy you're searching for, there's always the second brass ring of online retail – "Cyber Monday," or the Monday after Thanksgiving (Nov. 26 this year). Retailers see this day as their first opportunity to target holiday shoppers trapped at their work computers, so a lot offer additional promotions. The Black Friday trick of shopping in the wee hours can also help you snare Cyber Monday deals starting at 11:59 p.m., Sunday, Nov. 25.

Clean your cookies. Retailers base a lot of their online promotions and price points on shoppers' habits. So, it's not uncommon for shoppers to notice price fluctuations after repeated purchases on the same site. Prices typically drop for these power shoppers as an incentive, but there have been documented occurrences of increases, too. You can check to see if this is happening to you by logging out from the retail site, clearing your browser's cookies, and then revisiting the product page. If you find a lower price, buy it – re-registering with a new customer account if necessary.

Don't miss out on free shipping. Subsidized shipping has become the ultimate boon for holiday shoppers, but it comes with a catch. Many retailers only offer free shipping as an incentive to early shoppers. So, it's crucial that any online orders are placed by the industry-benchmark date of Dec. 12 to take advantage of these offers. After that date, be prepared to pay through the nose for shipping, especially if you want your purchases to arrive before Dec. 25.

Buy refurbished. Another dark horse when it comes to netting some of the best online promotions is finding an online retailer that specializes in factory-refurbished equipment. Not only are the discounts deep, but the merchandise is often sold in virtually new or "like new" condition, and additional promotions may cut your costs even further.

Jennifer Canty, president of refurbishing retailer Dyscern, says that the real challenge is finding a retailer you're comfortable with. "You want to investigate the retailer, and make sure they have a good reputation," Canty cautions. "A lot of refurbished-equipment sellers are also sellers on eBay, so you can check out their ratings and get a feel for them." Also check for warranties and money-back guarantees, and make sure you read the fine print.

Sure, you're just playing into the merchants' hands when you take advantage of discounts, coupons or other shopping incentives. Retailers ultimately want one thing: consumers to snap up their inventory and hand over the credit card authorizations. But if you can intelligently navigate the maze of discounts and promotions, that can work to your advantage, too.