There are many places where one can buy casters and cart wheels online. This includes sites such as 'Castors Online', 'Ross Castors' and 'Wheel and Caster'.
You can purchase utility carts with wheel online or at any hardware store near your location. These are inexpensive and and be found online or a home depot.
The website of the company who made the grill. Or eBay
You can find the best rates for casters if buying in bulk online. One such site is http://www.acecasters.com/products/specialofthemonth.html.
You can find industrial casters at any store's (such as The Home Depot or Lowe's) online website. You can also search other sites such as gilmorekramer.com, if you don't want to go to a corporate store site such as those.
Many stores carry casters, it all depends on what size and type you need. Here are a few vendors to check: The Home Depot, Office Depot, Amazon.com, and Sam's Club.
There are several places where one can buy a coffee cart. Some of the online places are: eBay, Amazon, Coffee Cart Biz, Coffee Bella, Alibaba and Gumtree.
Heavy duty swivel plate casters could probably be the best choice but medium duty swivel plate casters would also work. Globalindustrial.com is a great site if your looking to buy online. Your local department stores will also carry them.
You can buy wheels or tires at pretty much any tire based website. Try going to Michelin.com, or TireRack.com.
TSW Alloy Wheels are available at many online and offline stores. For online orders one can use sites such as Amazon, Buy Wheels Today and Wheel Fire.
Yes! Casters are an absolute must. Casters will make your office space much easier. If you buy a low-profile chair with no casters, then moving around your desk will pain since you'll have to bend or try to reach something without moving you chair. My point is that if you're going to buy a executive chair for your office, save up money enough to buy that swanky new chair with casters than a bad chair that will slow you down in your work.
There are literally hundreds of places online where one can get custom wheels. Some of these places are Tirerack.com, Tirekingdom.com, Rimfinancing.com, Completecustomwheels.net and customwheel.com.
You can buy laundry carts on wheels in stores and online. You can go to walmart or walmart.com, target or target.com, ebay.com, amazon.com, or buy.com.