Core vendors:
These are vendors that are active in the mini-z scene and add alot to the hobby with their innovation and services. Support these vendors whenever you can. There are overseas vendors with lower prices, but when add in shipping, usually, you end up saving just a few dollars. I would rather support domestic hobby stores.
Kenon Hobby- Located here in California that specialize in mini-z. Know for their race proven parts, and always fully stocked. Is the distributing arm of PN Racing. The owner Phil takes a lot of effort to organizes the annual Mini-z World Cup races around the country. Mini-z race first Saturday of every month at the store. Pretty good turnout every month.
Tinyrc.com - This shop runs the well known Mini-Z Racer.com forum. You can find answers to almost any questions about Mini-Z here. The shop have a large selection of Mini-Z parts at good price and excellent service with low shipping cost. If you shop there, make sure you use the express list function so it only shows what is available. Otherwise, is very frustrating to scroll thru many pages of out of stock items. A popular item is the Racing Dry Bearing.
Reflex Racing Joe and Christian runs the shop. They are both heavily involved with racing. They spend a lot of effort promoting mini-z. Popular place to get parts and advice.
Atomic Mods - Specialize in electronic upgrades to Mini-z and Xmods. Good tutorial sections on how to FET a mini-z and LiPo batteries conversions. They have an in-house factory driver Cristian Tabush that tests and fine tunes their products.
Overseas vendors:
Hong Kong vendors have good prices, but shipping is high, and takes a while to ship.
RCStation Racing - Very competitive prices but high shipping
Dinball - Good prices. Large variety of parts.
RCXMini - Good source of parts
EGR Racing - Good variety of parts
Hobby Link Japan - Has some of the impossible to find part that are only available in Japan. However, their mini-z list of available parts is not that long.
Hobby Japan - Sell many original Kyosho parts on ebay for reasonable price. You do have to add shipping from Japan. You end up not gaining too much.
Rainbowten - Like Hobby Link Japan has many mini-z Kyosho parts, but at very competitive prices. Don't know how much shipping is, but they said they only charge exact shipping amount.
RCmini-z.com - Japanese source like Rainbowten. Never tried them before, but looks like they have a lot of items for sale.
Cargel - Sells polycarbonate bodies and mini-z parts.
http://www.rc-champ.co.jp/ - Place to get 1/10 scale rc cars email them at champ_international at yahoo dot co dot jp
Other vendors:
Kyosho America - Don't forget the official Kyosho store. Large variety of parts and well stocked. There has been complaints that some items are sold out without telling you on the web page. I had that happen once, and end up paying the high shipping for only one part. Still a good source.
Hobby Etc- Sells mainly GPM products. Large selection and some parts that are hard to find elsewhere. Usually, hard to find parts are the less popular parts for one reason or another. Either too expensive, not necesary or no performance advantage.
ToyEast - Sells the copy cat IWaiver 02. Is the copy of MR020. Known for glitches in electronic and inconsistent quality. May be good to get started cheap, race for a while and decide if you like it then upgrade to Kyosho.
Micro Motor Parts - Not many parts, but have a few bodies and ready to run.
Z-Speed - Manufacture of some unique products like bearing mount tool and tire truer and custom rims.
HKS Hobbies Here is the place to get all the Atomic parts. They are the official dealer for US. Great selection of Atomic parts. Looks like they stock everything that Atomic makes and many bodies also.
Performance Xmods Do not sell Mini-z, but have very high performance motors. X-1 and High Standard V4 are suppose to be very fast.
Multiverse Interesting parts for mini-z in Japan.
Performance Devices Place to get high quality AM crystals for the radio.
Specialized vendors:
Acer Racing Sells hard differential balls - Kyosho differential use 3/32 balls.
Buy Reliant.com - Cheap Power Supply for Chargers - If you have a high end charger like the ICE, you need a powersupply. Here is a good one for cheap.
Carbon Fiber Chassis European site, but will sell to US. Money no object carbon fiber mini-z chassis. They have an electronic regulator (Regler) that would be useful for mini-z using Li-Po to regulate the voltage so you don't fry the circuit board.
ikinari - Sells TaGu parts for highly modified mini-z
Iwaiver Competition to mini-z with lower price. Quality has been questionable, but improving.
QTEQ - Japaneese firm that make very unique products for Mini-Z and other scales.
RJR Cool Tools - They have Moody JIS screwdrivers. JIS screwdrivers are the ones that fit mini-z screws perfectly. They use a Japanese standard. Moody screwdrivers are high quality, and don't cost that much.
Rony - Japanese company sells a lexan pan car body for mini-z
Skynet (Aoshima) - Maker of interesting mini-z bodies like Batmobile, Mad Max and Back to the Future cars. You can get their bodies at Hobby Supermarket HW Japan which is the official outlet for Aoshima.
TGR Custom carbon fiber chassis for mini-z
Thomas Distribution Sells batteries and chargers.
Turnigy Charger - At less than $40, it is the best deal professional charger out there. Chages Li-Po, Ni-Cd, NiMh even LiFe. Has Li-Po balancer build in. Mini-Z don't use Li-Po, but if you venture into airplanes or helicopters like many people do, then haveing a charger that does it all is handy, and saves you money in the long run. However, keep in mind that the baseline charger is only good for 50W. That means if you have a 3S Li-Po pace with 11.1V, you can only charge up to 4.5A. (11.1V X 4.5A = 50W) That is good enough for most moderate application. If you are into 4S packs with 14.8V, then you are limited to 3.4A. That is 1C charging for a 3400 mah pack. Not quite enough for high power full size remote control airplanes.
Vapex 1100mah AAA batteries. Great batteries, but expensive shipping from UK.
Wild-Z Racing Sells TaGu custom wheels and parts. Can order custom wheels in desired offset. Expensive though.
Woah Nelly - External FETs - Handle lots of power by piggy backing a speed control outside the electronic box.
Pro-Z - Highly modified graphite chassis
Turborix - Forget Futaba, best deal programmable 6Ch 2.4Ghz radio for only $43. Programmable on your PC. If you are looking to try airplane or helicopter, and need a radio, here is one that will do everything for you. Amazing what free trade will do.
Cargel - Lexan bodies for mini-z
Bad Horsie - Sells socks for shocks (Not applicable to Mini-Z), but also sell a very heavy grease that can be used to lock the diff.
Custom Decals - Will make decals for you
Carpet for building tracks - Calandra Racing sells carpet for r/c car racing. Can also use popular Ozite carpet.