The armorer is the master of producing heavy and medium armor for both fighters and priests. While the profession is of course open to any who choose it, for characters who want to boost their adventuring class, it's ideal for fighters and priests. This is quite an interesting profession, and if you make friendships with characters who need what you produce, you'll be able to get repeat business providing armor that meets their changing needs. The profession becomes more profitable at the higher end, as you start producing armor with various resistances that raiders will need. Imbuing armor also helps to make it more powerful. Combined with the transmutation secondary profession, you'll find that being an armorer has some serious perks.
One thing that you should know is that raising your armorer skill will be expensive unless you gather the materials yourself. Actually, it's expensive even if you gather the materials, because you could have otherwise sold them for a profit. For professions like armorer, it's sometimes wiser to level up your adventuring class before you start to tackle the artisan part of things. At higher level, you'll have an easier time harvesting resources, as you'll have a better mount and access to the higher tier materials. The only issue is that you miss out on being able to craft your own armor - but while your leveling, the rewards from quests and drops are sufficient to keep you competitively equipped. It's of course up to you - you can focus exclusively on your artisan profession if you wish, although it will be a more challenging path unless you spend lots of time performing tradeskill quests.
Pristine is the highest quality of armor that you can create, and you need to complete the crafting minigame without any mistakes in order to get at it. If it takes you a while to learn how to do that, don't fret - you have plenty of time to master it while you level up. There are hundreds of armorsmithing recipes, and it helps to learn all of them. If you're in a guild, one helpful thing to do is to make armor for your lower leveled members to help them get up to speed. Crafted armor in EQ2 is just as good or better than drops the same level, at least for the most part. Armorers can also put together armor blanks that are dropped in raid zones given that they have the right materials to add to them. Good armorers can do this job for either their guildmates or others, making a healthy profit in tips just for making the combine.