Now let's move on to the actual oil paints! Feel good about this--oil paint is a fantastic, wonderful medium. It has a *huge* history (and therefore a *huge* amount of visual and technical reference), there are a million ways to approach it, it gives singular results...and it can be your lifelong frenemy and challenge-agent.
First, let me mention that what I'm giving you here is the Quick & Dirty; it's by no means the long-form on anything technical. I'm going to give you a basic grasp of the most important and most used concepts and advice--straight from my personal experience--to get you up and running (and most importantly: to get you experimenting for yourself). If you want to go deeper, take my advice and get a copy of Ralph Mayer's, "The Artist's Handbook of Materials and Techniques". You may have heard of it; it's the artists Tech Bible. http://www.amazon.com/Artists-Handbo.../dp/0670837016. It's less than $30, new.
Let's break it down:
• Ingredients: Oil paints are mainly composed of these two elements: Pigment (powedered color), and Vehicle (linseed oil--the "oil" in oil paints"). Metaphorically speaking, think of a sandwich. Your pigment is the meat and the vehicle is your bread. When you add medium, turp, drying agents, etc--those are the condiments.
• Paint Brand & Quality & Price: Always buy the best you can afford. Always. The best oil paints have more pigment, better quality vehicles/binders, will be more lightfast, and will look richer and deeper. I use Winsor & Newton Artist' Oil Colour almost exclusively. They run between $6 and $46 for the 1.25 oz (37ml) tubes. When you're starting out, a lot of the $6 paints are all you'll need. Over time, spring for a $46 cadmium or cobalt once in a while; you won't feel the $$ pain too much that way. (I'm currently using a couple of Winton (W/N lesser-grade) and Liquitex colors since I have them.) Higher permanence (A grade) and higher series (4) cost more. Cadmiums and Cobalts (heavy metals that comprise the pigments) also cost, but are worth it. Get the best you can afford, then forget about it and paint.
• Color (local color, hue): The basic color of the paint (red, blue, green, etc).
• Tinting Strength/Saturation: How potent the paint is. For example, if you mixed a pea-sized blurp of Pthalocyanine or Winsor Blue into a cup of white paint, the mixture would turn out *quite* blue. If you did the same thing with Davy's Gray or Terre Verte (common under-painting colors)--it would not tint the white much at all. This is important to know when you're mixing; sometimes you need the "acidity" of a high-tint color, sometimes you need the resulting mix to sit back and be duller. Tint Strength also comes into play (as we'll discuss at a later stage) with Glazing.
• "Chalkiness": Technically, the term is "Opacity", but chalky is the word I use in my head when I'm thinking through a paint mixture. (Here's why: paint opacity can be manipulated depending on a number of factors quite independent of the color's original Covering Power and will vary depending on how much medium you use in the mix and how you apply the paint with your brush.) Examples: Cadmium colors are chalky, as is Oxide of Chromium (Green). You can experiment and mix chalky/chalky, chalky/unchalky, and unchalky/unchalky--I'm not making a rule, or anything; just be aware of how they interact and use them to achieve your desired results.
• Temperature: Refers to which "side" of your Absolute Color the paint lies. For instance (using ROYGBIV): Blues; Manganese Blue is warmer (tends towards green) than Ultramarine (cooler; tends towards indigo). I mostly lay out my paint on the palette following temperatures (unless I run out of room when adding a new color).
• Resources: I'm not shilling for any particular brand or company, but having said that...f88k it, and here are some useful links to give you some idea as to the specific costs and properties of some of the things I've been talking about.