Models & Customizing - General/Other - Fanart & CGI/3-D - Anime
Models & Customizing

Age of War is Maethius’ custom Zoids site. Lots of great builds here, with their own version of Planet Zi and story to go with them.- Blueeyesgirl3's Zoids
Pictures of and info on Zoids models. - Channel Zi
Like a phoenix from the ashes, but with more Thunderball…it’s back. Again! Channel Zi was one of the sites for a lot of the fandom that rose up from the anime hitting the states, and it’s great to see it return. - Deathy's Empire of Nyx
Guess who it’s owned by! Kidding, kidding. Deathy’s got reviews of Zoids for your Zoid review-reading pleasure. 
Gojulas’ Lair is back online, now sans frames :D. Model photography, customization, and some fixes for Zoid issues.- Ironwing's War Room
Ironwing’s War Room is now back online, with the older content also available. Lots of info on Zoids releases in a searchable format. - Jeoren's Expanded Zoids page
Another classic site, including info, pics, and movies of regular Zoids and customs. - Mister Hook's Zoids and Robostrux Site
One of the best resources for photos of obscure things like…well, Robostrux. - OcellatedStingray's Zoids Site
Lots of reviews and collection pics, organized by type of critter. - Pimp My Zoids
A customizing blog with construction posts, not just finished Zoids. Be sure to check out Wu! - Rabbit Lab
Bluedemon’s site, which features a number of great customs, including Racing Mecha Chocobo, the winner of the 2007 racing contest. 
Natsumi’s site. Zoids and other things modeling (and art), including customs and painting tutorials.- Shadow Blade Zoids
Risky’s Zoids site with customized models, occasional regular models, and fanart. 
Hidocker’s site is mostly unusual and/or interesting photos of Zoids with amusing commentary…and very nice WordPress usage, unlike mine :p. The world needs more of this.- Striker Unit
Crushader’s Liger collection—just Ligers. Lots of them, photographed and on display. - The Deal's Wheels Web Site
Darth Tres’ site, with nice photos of customs and stock Zoids alike (mostly older releases). 
GhostLiger’s collection site, with reviews and such fun things.- Ultrasaurus Red
Lionel’s chronicle of all things limited and obscure, especially the fabled Ultrasaurus Red. And customs. Cool customs. - Z's Zoids Site
Collection pictures arranged multiple ways—and with a definite focus on the motorized Zoids. 
Zoid.US has lots of content, including construction-oriented reviews of many Zoids kits and info on prototypes and other obscure things. See also: BattleRex.com, Wikd’s Zoids blog.
Zoidology is the new home of Zee Wakusei’s customs. His work is mentioned a lot in the English-speaking Zoids fandom, and for good reason.- Zoids – The Pre-Hysterical Monster Machines
Mike’s site. He loves Command Wolves, especially chrome ones. He’s also got some nice photos of his own collection, including lots of OER. - Zoids Fusion Lab
Solloby’s blog o’ reviews, with a bit of a focus on Blox and their combinations. - Zoidsism
Custom Zoids by Nobody-Here with some very nice color schemes.
General/Other

Momonga has battle story translations and other things Zoids.- Sieg.nu
Zoids doujinshi and card game scans—lots of card game scans, from multiple variations of the card game. 
Info on all things Zoids, though with an emphasis on the more obscure.
Zoids Evolution is back, complete with properly hosted forums and general Zoids content. It’s pretty slow these days, but still around!
Zoids Lair is a general site with some focus on the games (and the sprites in them).- Zoidstar
High-res scans of the entire UK Zoids comic. If you haven’t read it yet, you must.
Fanart & CGI/3-D
- Andy Whiteley.com
3-D modeling and animation, including a very sleek Gore (in Iron Kong Yeti colors). 
Cap’n Dade’s Place has custom Zoids and CGI, something you don’t see very often on English fansites.
Jam’s Art Blog contains Zoids, Hetalia, and original art.
Qzei is Momo’s art site…with a lot of Zoids, among other fanart and original things. Contains high amounts of battle story :3.
Stompy’s Custom Zoids is home of the Cannon…er, Blitz Panther and a number of other original CGI Zoids creations.
Zinou’s Webpage is home to much headcanon. And Zinou draws pretty stuff (and by pretty, I mean awesome and often bloody).
Anime

Blue Sky, Jammer’s O’Connell shrine/general site in one. Also has forums.
Liger’s Union, another anime fansite that’s stood the test of time. HaTcH has lots of amvs and screenshots, all at high-quality because of his DVD-ripping powers. Now with an interactive fanart gallery in php.
Masters of Zi has general anime info—plot summary, character profiles, and such. Also has a database of Zoids Legacy stats!
Zoids Tribute is one of the only classic sites left with anime info (including dub/Japanese comparisons from a Japanese perspective). The Japanese version has different content and is worth a visit too.