Reasonable people understand this by now: environmentalists aren&'t all tree hugging vegetarians with unwashed hair �a4���a4� not that there&'s anything wrong with that �a4���a4� and tech enthusiasts aren&'t all oblivious to the burgeoning problems of energy consumption and e-waste. Still, it&'s tough to shop online for geeks who want to be environmentally responsible, and nouveau hippies who covet gadgets.

Why It&'s easy to find green gifts in the beauty, fashion, home or kids category. Many retail websites, however, bury their great green electronics pages rather than highlighting them, and making them easy to find from the homepage.

We&'re looking at you, Target, Walmart, Sears and BestBuy, sites that don&'t have green tech or eco-friendly sections or search filters that make it easy to find the water-saving, solar, LED and more earth friendly tech items they carry.

Maybe big retailers don&'t want to come off too specialized, or maybe they&'re worried about implying other products they sell, outside of a special &''eco&'' section, are somehow environmentally wasteful.

Let&'s admit it. Some of those electronics are wasteful. A wino, or possibly an arthritic sommelier could make the electric corkscrew worth its weight in rare earth metals. But who really needs a portable watermelon cooler

Gift shoppers can&'t rely on the media&'s picks entirely, either. Several guides have recommended stuff this season that&'s either utilitarian, or expensive enough to wilt mistletoe.

Treehugger suggested a $670 eMeter that measures a users&' energy consumption at home. Inhabitat suggested a water clock that duplicates time-keeping features of a basic mobile phone�a4���a4� but hey, it runs on lemon water so it&'s &''eco.&'' The biggest stinker was NetworkWorld&'s recommendation to give the automatic, electric composter as a gift. Who&'s naughty enough to get that one (It&'s not even solar-powered!)

The most environmentally friendly gifts one can give are probably not things �a4���a4� shipped from far away, delivered by diesel trucks, destined for the landfill �a4���a4� but digital goods, like a must-read e-book or a membership to a streaming video site. We know.

Digital goods lack that whole je ne sais quoi of handing a loved one something they can tear open. Hopefully, it&'s wrapped in 100% recycled and recyclable paper. We suggest using the comics section�a4���a4� save a tree and a little piece of the print news business.

Here at TechCrunch, we found a six-pack of sites that either specialize in, or have designated sections and great search filters for what we call green tech. These should help you find sustainable gifts for tech heads that are actually worth coveting, and should arrive in time for Christmas if ordered on or before December 15th.

2. GoGreenSolar.com is a specialty store with products to please home improvement and gardening enthusiasts, from a solar power generating system that doubles as a back yard cabana (about $10,000) to efficient LED grow lights for budding botanists ($30 and up).

3. Amazon.com has a special Amazon Green section. It&'s not featured in home page navigation, but a quick search on the word &''green&'' leads users there. The special section&'s Green Electronics category features everything from energy-efficient laptops and netbooks to information on recycling the old to make way for the new.

4. The Overstock.com electronics section includes quick links to &''Made in the U.S.A.&'' gadgets, and &''Refurbished&'' items. Refurbishing is recycling, which makes it automatically green. Buying locally produced anything tends to eliminate emissions generated in shipping from far away. The United States also has stricter environmental regulations than China and other exporters.

5. 21st Century Goods, a specialty retailer focused on &''off-the-grid&'' lifestyles, offers plenty of cute eco-friendly gadgets, from hand-cranked mini-USB device chargers ($14) to solar-powered flag pole lights that would make a good present for a proud patriot ($60-$130).

6. Dont&' let the yoga mats scare you at Gaiam. The sustainable web store also sells: recyclable water filters for home chefs and health nuts who crave pure hydration' energy-efficient hair dryers for the style addicted, and for the outdoor adventurer, a hand-operated, snake bite and insect poison extractor (a weird and inspiring stocking stuffer).

Also worth noting:

For gift givers across the pond, this site delivers eco-gadgets to the Euro-paying market: EthicalSuperStore.com.

For a guide to what&'s hot in tech in general this season, visit Crunchgear&'s 2010 holiday gift guide.

Beer can wreath image via Krupp

Charlie Brown-style Christmas Tree image via Listen2ds