(I'll start off with this by way of full disclosure: I freaking love working with ritual tools. And I'm not even sorry.)
The first formal magical training I had was in the Outer Court (or pagan grove) of a Gardnerian coven, and the first formal magical tool I acquired was an athame, the ubiquitous ritual dagger now commonplace among all sorts of pagans. (Athames--not just for Wiccans anymore!) Prior to this I had very little by way of ritual equipment, using whatever seemed appropriate for the spellwork I occasionally performed as well as for any formal deity propitiation I felt necessary. Prior to entering the grove I had read about Wicca/witchcraft/paganism and its associated accoutrements, but I'd not bothered to acquire much of anything beyond the basics.
That was about to change.
I was serious about the pursuit of Occult Knowledge, and if said pursuit required tools, then I would acquire tools. Off I went to a military supply sort of shop in the local mall--because where else would you go to look for such a thing as a dagger--and located what seemed like an appropriate knife for the purpose. I didn't want to buy just any cheap piece of junk; that didn't seem serious to me, and I am a very serious sort of person when I am inclined to be. I chose a simple Western Boot Knife, which cost the seemingly exorbitant amount of $40.
I'm sure some people purchase one athame in their magical career, and keep it for the rest of their lives. That's great. That's not at all what happened for me. (Did I mention that I ended up dating, and then marrying, the guy who introduced me to the pagan grove, and that he was and is a blade connoisseur? No? Oh.) I worked with that first knife for a time, and then it was passed along to a dear friend and I chose another athame. And another, and another. I was initiated in 1994, and since then there have been a number of athames that have passed through my hands. At present, I have (I had to actually think about this for a moment) three that I work with regularly, though each has a specific function: one for witchcraft, one for general pagan usage, and one for travel.
I've long since left the tradition in which I trained, going on to develop, with my partner, our own way of doing things. For us, the athame is not just the tool of Air, but is considered the Key to all the elements. It is a powerful and important tool, and thus it needs to be a tool with which one can bond, and for which one can feel respect. If I'm going to use a tool, it needs to be real and functional and solid right here on the material plane: the "so below" is just as important in my workings as the "as above." (I was born under the cardinal sign of Earth, and have a lot of Earth in my chart; and while I am unconvinced of the extent to which such things genuinely influence us, you may nonetheless take those facts into consideration for the purposes of this particular discussion.) Good ritual for me is in part good drama, and if my props are crap, it impacts my work at a very visceral level. Sure, I could cast a damn circle with a butter knife I grabbed out of the kitchen drawer, or a pot-metal letter opener, if I had to; but if I don't have to, why should I? In truth, I'd rather point a finger and do my operations on the astral rather than use a tool in which I have no confidence.
Before I started this post, I debated on whether to make it informational or personal; as you can see, I decided on the latter. There are approximately 87 billion sites out there that expound upon the subject of the athame, what it is, how to use it, its elemental ascriptions, how to pronounce it, what shape it should be, what color the handle should be, what type of blade it ought to have, etc. You don't need me to tell you all those things. Start off with the understandings of the tradition in which you're training, or with what you've found in your print sources that resonate with you. As time goes along, you'll gain your own understandings and meanings, some of which may enhance what you've been taught, some of which may contradict what you've been taught, and some of which may ultimately supplant what you've been taught. It's all to the good. This kind of work is evolutionary, not static.
And that's why your magickal toolbox may end up a bit fuller than you first imagined.
(The knives are: top right, Western Boot Knife, stainless steel blade with rosewood scale handle. Middle left, athame by Rod Matless, stainless steel blade, black bog oak haft, nickel silver guard, sterling Celtic ring ferrule, nickel owl head pommel with garnet eyes. Bottom right, Moon and Star athame by Gary Zaradkha. Carbon blade with bronze guard and pommel, carved Dymondwood handle.)