Just surfing Wowhead, and I came across Item Sets.

So, what exactly do I have to do to get a complete set like

http://www.wowhead.com/?itemset=205

for example?

Beg, borrow, steal?
Live, breathe, BE Warcraft?

First of all you are not likely to ever get Tier 1, Tier 2 or Tier 3 sets as they are from "old world" formerly end-game content. IOW, finding a group to run thru MC a dozen times just ain't gonna happen.

Check out the Tier 4 -6 sets as they are the "new" sets included in BC. You obtain these from boss drops in end-game RAIDs (Kara, SSC, Gruul, etc.). Just look at the wowhead data and it will give you an idea of which boss drops which piece. Actually, the boss drops a "token" which is used to purchase the item from a vendor.

There are "Dungeon Sets 1-3" as well. DS1 and DS2 are old world sets, whereas DS3 is obtain my getting drops from regular 5-man instances in the Outlands.

Other non-drop items sets exists as well, including those from leatherworkers, tailors, etc.

Other non-drop items sets exists as well, including those from leatherworkers, tailors, etc.

Sadly it seems most of the nice purples are BoP so if your not a LW you are out of luck on them. I know most of the Feral items I am working on getting are all BoP, not sure about the healing gear items(will make them once I have extra primal's for a back up healer set).