Now that you have the addons and the websites needed for success, you are ready to make auction toons. You will want two auction toons, one on the same faction as your main toon and one on the opposite faction. Do not use your main toon to make the auctions that get you gold! This is one of the greatest mistakes you can make because after a while, people will get annoyed with your prices and selling quantities and begin to blacklist you from groups and some will even boycott your products. Do not risk this happening to you, but rather, create an orc for horde and human for alliance and get them outside the nearest auction houses in Orgrimmar and Stormwind respectively. (As a personal preference, I tend to avoid names with bank, mart, or sell in the name because when negotiating outside of the auction house, you seem less personal). All the addons we downloaded should be enabled for these characters as well.
Once you reach 575 you can purchase vendor recipes for the last 25 points. The Blacksmithing recipes are on a vendor in Vale of Eternal Blossoms. You can enter Vale of Eternal Blossoms after completing the questA Celestial Experience (requires level 87). After you completed the quest, you can find Jorunga Stonehoof (Horde) in Shrine of Two Moons and Cullen Hammerbrow (Alliance) in Shrine of Seven Stars.
Soloing an instance can be all the more profitable if your character is an enchanter. During any solo instance run, you'll end up with some items which can be sold or traded, and some that are bind-on-pickup. Non-enchanters can only sell these soulbound items to a vendor, but an enchanter can disenchant the bind-on-pickup rare items, and then sell the shard/dust/essence instead of just selling the blue item to a vendor. (A side benefit of selling enchanting materials is that they do not require a deposit to list in the auction house, allowing you to list endlessly until the item sells.)
Only really to expand on Gráinne's comment as regards the 'collecting' and 'roster development' sections - which are, as said 'distinct' although they are intrinsically linked - I would like to point you in the direction of the in-game Achievements > Battle Pets > Collect tab. There are a series of achievements called Raiding With Leashes, pretty much all of which can be completed via the auction house - if you have the gold/inclination - or by completing old raids.