1) Knives and a sharpener - Every butcher needs a few essential knives. For starters, you'll need a good field dressing knife (if you deer hunt, I'm sure you already have one) so probably not any ground breaking news here. If you don't, one of my favorites are the Buck brand of knives. You'll want either a locking or fixed blade knife that has at least a 3 inch blade on it.
Second, you'll need a good boning knife. This knife will be used to do the majority of your butchering as it has a flexible blade allowing you to easily remove meat from the bones of the deer. The Mundial 5 inch boning knife is a great knife and fits any budget at around 11 dollars.
A third knife that I would recommend would be a Butcher knife; this is not an essential but it does make life much easier when trying to quarter your deer. The knife I use is made by Cutco and can be found here. These type of knives usually run around 100 dollars or so. This knife falls into the category of "purchase once you have everything else you need to make your life easier!!" Another example is the Victorinox Butcher's Knife, with a purchase price around $50.
Now once you use your knives, they will dull over time and you'll find out that the easiest way to cut yourself is to use a dull knife! In order to keep your collection in working order, you'll want to purchase a sharpener of some sort. If you go to your local sporting goods store you'll find both electric and block stone sharpeners. I prefer the manual stone sharpeners as they allow you to sharpen a variety of knives easily and effectively. Bass pro sells one here.
2) Bone saw - A deer can be quartered without a bone saw, using just a knife to dislocate the joints. Although the latter method is effective, it is quite time consuming when just starting out and takes some practice to get it correct. With a bone saw, you can make quick work of the hind quarters of the deer among other tasks! BassPro also sells one here.
3) Game hanger - A game hanger is a basic piece of equipment that everyone needs. This will be used to hoist up your game so that you can skin and quarter it easily and keep it off the floor out of the dirt and grime!
4) Meat grinder - The grinder is going to be the most expensive tool you'll need to purchase. Grinders have a very large range of prices ranging from $50 to $700. A hand grinder works but will require some muscle to use (if you only do a deer or two a year and just want to do burger this might be the best choice on a budget). A cheaper electric grinder that has plastic gears internally will also work but don't be surprised if you break the gears during heavy use or doing sausage. My honest opinion is spend the money upfront and buy one of the LEM grinders here. I have the .75 HP model and it works great for everything! The LEM models have all steel internal components and offer every accessory you can imagine. You can usually find great deals on these during the Holiday seasons!
5) Cutting boards and table - Any table will do...really! Just ensure that it cleans up easily! It is a good idea to purchase a nice cutting board or two so that you have a good solid surface to cut on without marking up the table you are on. The ones I use are available here.
6) Sanitary supplies - I find it's much easy to cut when wearing latex gloves. You can find these in the pharmacy section of most stores. Wearing the latex gloves allows you to keep a good grip on what you are cutting and allows you to remove and replace gloves without having to wash your hands all the time when going from task to task.
7) Vacuum Sealer - These are great! A vacume sealer will prolong the shelf life of your game in the freezer almost double what it would be in any other method of storage. Now, if you don't want to spend the money up front you can wrap your meat in platic wrap and then again in freezer paper. This method will give you a good shelf life and is quite cheap. However, if you want to really get the best "bang for your buck" then you should look into a sealer. FoodSaver makes multiple models in all different price rangers.
I've now covered what I feel you'll need to get started! Please feel free to post any questions or comments and I'll answer them the best I can. I have quite the collection of knives, sealers and grinder accessories.