Season 3 gear and season 2 gear are available for purchase in area 52, Nagrand near the Nagrand arena. Additional season 3 vendors can also be found in shatt in 3 areas. 1 near alder hearth. 1 near scryer hearth. 1 near the goblins who let you queue for arena.
Season 2 and season 3 gear cost arena points. Season 2 is half off. Season 3 is full price, with rating requirements for shoulders and main hand weapon.
Season 1 gear, along with season 3 honor gear, can be found in SW champion hall, and in orgrimmar, though I am unfamiliar with the name of the exact location. Season 1 gear costs honor.
When season 4 is released in the near future (no date or time yet, but will happen will sunwell comes out), season 2 gear will cost honor instead of being half cost arena points. Just something to be aware of.
Another thing to be aware of, is when season 4 begins, you will be able to buy season 4 gear. However, they will remove season 3 honor gear. So if you do not have the best luck, I would personally suggest picking up the season 3 ring so that you can acquire both season 3 and season 4.
Many people were upset that they removed season 2 ring when season 3 was released. So I figured I’d bring that to attention. Especially since it is possible to wear season 2 and season 3 rings at the same time. Where in the future it will be season 3 and season 4 rings instead.
Personally I suggest running Kara or ZA for your weapon, as the season 1 weapon (epic quality one, not to be confused with the blue one that can still be bought at a greatly reduced price) costs a large amount of honor, and is roughly the same as a Kara weapon, and slightly worse than a ZA weapon.
If your luck is terrible, you could grind honor.
If you wish to grind honor, I would suggest spamming AV only even after you get 100 marks. Do your spirit tower daily quest for 800 honor. If possible, do the daily hellfire tower quest for another 800 honor. As well as doing the BG of the day quest.
Personally, as a pvper, I think the honor grind is tedious, boring, mind numbing and toxic. Its slow, stale and quite frankly too long. So I personally wouldn’t attempt to grind it as fast as possible. You’ll lose sanity that way. I’ve grinded honor on 3 characters and its not fun. It’s quite frankly terrible and if it wasn’t a forced requirement for arena game play, I wouldn’t do it. I go lengths to explain this as I wouldn’t wish for any one to suffer or endure the agony that is the honor grind. So if you do, God speed and good luck.
Lastly, make sure to make a 2s team and play 10 games a week for around 270 arena points. You do NOT have to win in order to get your arena points on Tuesday. However, the higher the rating, the more points you will get.
It is, in my opinion, best for you to save your arena points so that when the season ends, you can buy season 3 gear for half off. Once the season ends, you get one week to spend your arena points. After that week passes, any remaining arena points will be converted to honor. Rating restrictions on weapon and shoulders will also be removed from season 3 gear when the season ends.
When season 4 is released, season 3 and season 4 gear will cost arena points. Season 2 gear will cost honor, and season 1 will be removed from the game.
Note that the honor pieces consist of neck, back, wrist, waist and boots. These pieces will always cost honor. Never arena points. The 5 set and weapons cost arena points, unless its an older season as explained above.
I hope this information helps. I would help with the other questions, however, I know not the answers, so I hope this will help you in your decision making.