For the Hoity-Toity Bookshelves
Even if you don't really ride or know how to read, you may still fool your friends on both counts with a collection of these books in your genuine Hoity-Toity Brand bookshelf or on your matching Oooo-La-La Brand nightstand  (many have lots of pretty pictures!):

Bicycle Routes on Public Lands of Southwest Colorado, 3rd Edition
    Bill Manning & Tom Harris / San Juan Mountains Association / Durango, CO

BLM Colorado: Mountain Biking Adventures
    U.S. Bureau of Land Management

Colorado Gonzo Rides: A Mountain Bikers’ Guide to Colorado’s Best Single Track Trails
    Michael Merrifield / Blue Clover Press / Monument, CO

Front Range Rider: A Mountain Biking Guide to Northern Colorado & Southern Wyoming
    Anne Childers / Poudre Canyon Press / Ft. Collins, CO

Front Range Single Tracks: The Best Single-Track Trails Near Denver & Boulder
    Tom Barnhart / Fat Tire Press / Littleton, CO

Front Range Single Tracks 2: The Best Single-Track Trails Near Denver & Boulder
    Tom Barnhart / Fat Tire Press / Littleton, CO

Moutain Bike Crested Butte, Gunnison & Salida Singletrack
    Holly Annala / B & B Printers / Gunnison, CO

Mountain Biking Colorado, 2nd Edition
    Stephen Hlawaty / Falcon Guide / The Globe Pequot Press / Guilford, CT

Mountain Biking Colorado’s Front Range from Ft. Collins to Colorado Springs
    Stephen Hlawaty / Falcon Guide / The Globe Pequot Press / Guilford, CT

Mountain Biking Denver & Boulder
    Bob D’Antonio / Falcon Guide / The Globe Pequot Press / Guilford, CT

Mountain Biking Grand Junction and Fruita
    Bob D’Antonio / Falcon Guide / The Globe Pequot Press / Guilford, CT

Mountain Biking the Roaring Fork Valley
    Richard Compton / WHO Press / Basalt, CO

Singletrack & Tarmac: Mountain Bike Trails & Road Rides in the Upper Arkansas River Valley
    Nathan Ward / Ice Mountain Publishing / Salida, CO
    (This is an updated version of “Salida Singletrack” by the same author.)

Tellurides: The Mountain Biking Guide to Telluride, Colorado
    Dave Rich / Wayfinder Press / Ridgway, CO

The Best of Colorado Biking Trails
    Staff / Outdoor Books & Maps / Adler Publishing Co. / Castle Rock, CO

The Mountain Biker’s Guide to Colorado
    Linda Gong & Gregg Bromka / Menasha Ridge Press / Birmingham, AL

For the Pretentious Coffee Tables
We mountain bikers take our coffee like our legs: strong, bloody, and hairy!!  (That's right, you sissy not-too-hot-chocolate-sipping roadies!)  Make sure your morning brew has some worthy company on your genuine Pretentious Brand coffee table with these select rags:

Bicycling Magazine     Bike Magazine     Dirt Rag     Mountain Bike Action Magazine     Mountain Flyer Magazine

Online Resources
"What?  You mean there're things on the internet besides... y-know."  Yes, my friend, as the modern-day library, the web holds an immense wealth of knowledge just a few mouse clicks away.  And all without that crazy Dewey Decimal nonsense or crusty old librarian always shushing you.

Makers of that thingy you sit on with two circles that go round and round:

Cannondale     Ellsworth     Giant      GT     Kona     Marin     Moots     Pivot     Rocky Mountain     Santa Cruz     Specialized     Trek     Yeti

Other fun and cool places on the web (hopefully more serious than here):

Bicycle Colorado: An advocacy organization dedicated to encourage and promote bicycling, increase safety, improve conditions, and provide a voice for cyclists in Colorado.

Bicycle Sherpa: A resource directory featuring current lists of organizations, races, clubs, bikes, parts, accessories and apparel.

Bicycle Site: A site created to provide information and resources to cyclists of all types and ability levels.

Boulder Mountainbike Alliance: BMA exists to serve as a positive voice for mountain biking by making the trails in Boulder County a better place for all users.

Colorado FrontRangers: An organization serving as an informational clearinghouse for social and recreational activities organized by its individual members.

Colorado Mountain Bike Association: COMBA is dedicated to protecting and improving mountain biking on the Colorado Front Range.

Colorado Plateau Mountain Bike Trail Association: COPMOBA acts as a positive voice for mountain biking through volunteer trail construction and maintenance projects, advocacy efforts, riding clinics, group rides and fundraising efforts.

Community Cycles: a non-profit organization founded to educate and advocate for the safe use of bicycles as affordable, sustainable means for transportation and enjoyment.

Dérailleurs: A French gay and lesbian cycling club, both mountain and road, that is based in Paris and has over 150 members all around France.

Dictionary of Mountain Bike Slang: Someone calls you a "fred."  Is that a good thing or bad?  Learn the language before you decide to whip out the knives or the hugs.

GoI70: A handy website to learn the latest and current traffic situation along I-70, the busiest highway into the mountains.

International Gay and Lesbian Outdoor Organization: IGLOO is an informal affiliation of all-volunteer organizations promoting non-competitive outdoor activities within the larger GLBT community.

International Mountain Bicycling Association: IMBA is founded to advocate for the rights of responsible mountain bikers around the world.

Mountain Bike Review: MtBR is an invaluable resource for trails and gear reviews, biker discussion forums, and other informative and fun features.

OaxacaMTB: A "Trailhead" for mountain biking in and around Oaxaca, Mexico, with maps, elevation profiles, trail descriptions, photos and more.

Out and About Colorado: OAAC provides an atmosphere of fun, friendship, and fitness to the gay community by functioning as a central information site for events in and around the Colorado Springs area.

OUTspokin': A group of gay, lesbian, bisexual, transgender, and allied cyclists in Colorado promoting positive gay and lesbian visibility and philanthropy by bicycle.  Our road biking sister club.

Outsports: When gays and sports finally mix, there's the Outsports website to handle it all.  Info on gay athletes, groups, and events.

Parlez-Vous Bike?: A humorous article (pdf format) by Scott Martin translating what bicyclists say to what they really mean.

Singletracks: An invaluable resource for information on trails, gears, news, maps, and other useful features.

Southern Colorado Trail Builders: The nice, hard working folks who built most of the singletrack trails in Lake Pueblo State Park.

Two Spoke: Bicycle forum and reviews for all types of bikes: road, mountain, BMX, recumbent, and more.