I don't know about kits for sale, but as far as helping with a kit it depends on if you are going to trunk or just where the charcoal canister sits. Either are possibilities. I like the trunk personally because it seems like a pain to get to at the other location. As far as parts, you don't need to amazon it, everything can be had at a local parts or hardware store.
Disclaimer!!! This is my method, it works well and I haven't had any problems with it. It looks clean and functions well but I am sure that someone in this thread will call me an idiot for some reason or other. Furthermore, I am sure that there are other/better ways to do it, but this is how I have done it in the past. It minimizes the amount of permanent modifications to the car.
I used about 20 feet of either 0, 2, or 4 gauge(not sure if this is large enough) wire that I got from a local audio spot. You can also use wleding cable, but I use this because it is very flexible and has good conductivity. I use the copper connectors that are sealed on the eyelet end, and fill it with solder. Then I strip the wire, add some heat shrink, melt the solder and insert the wire, heat shrink it...you can do this twice if you like also. Route the wire either under the car or through the interior if you like tearing up and reinstalling carpet. Then do the same on the other end. Get some sort of distribution block, or build one, and mount it under-hood. Make a shorter lead for the negative side of the battery and ground it to the frame in the rear. If you drill any holes, make sure to protect the wire and your trunk from moisture and from getting sliced by the sheet metal by using either a piece of hose that is cut as a grommet, or by drilling through the stock trunk grommets. Get a marine battery box and secure it in the trunk however you see fit. Secure your battery (I always use an optima yellow top since it is unspillable and has a great warranty) inside the box with either the j hooks or with straps. I always use quick disconnects with the butterfly nuts on the battery terminals. I like to use red heat shrink for the positive and black for the negative. You can also add a cutout switch inline on the positive side in the trunk, and possibly a high amperage fusible link if you want. If you are interested in pictures of how mine is set up I am happy to provide them, but I am not going to post them unless you ask.
Now, having said that, I think it costs about 75 bucks for everything. HOWEVER, this in not necessarily the very best connection for the ends. You can use crimps etc to get a better connection if you see fit. Solder is not meant to be the connection between the Eyelet connectors and the wire itself, it is just meant to hold it together and help keep corrosion out.
Once again, I am sure someone will call me an idiot and say that I am going to catch my car on fire, but I have never had any issues with this method. Best of luck and I hope this helps!
Cheers
-manik