Starting collecting the Black Series

I'm going to start collecting the 6" Black Series. I'm not going to go completest because how many versions of Luke/Han/Leia/Yoda/etc. does someone need? Some characters I really want to get are Kylo Ren, Ahsoka, Revan, Vader, Darth Maul, OK all Jedi and Sith in general, Han, R2, BB-8, Rey (hopefully with her saber), Finn, a few Clone's, a few IV-VI Stormtroopers and a few TFA Stormtroopers.

What are some of the better versions I should chase (probably on ebay) of older figures and what is a good place to get the newer figures from?

Lots of loose and KO BS 6" on eBay so be careful. I saw one vendor with Star Wals boxed figures, so just keep an eye out. Its been mentioned elsewhere on the forum, so if its too good to be true, it probably is. I know for some figures the after market price is quite high, and you may be able to fill the void with slightly more expensive, but better quality figures, like SHfiguarts or mafex.

figurarts is the way to go! thou darth maul black series is awesome cos he has his hoodie :)

By far the best TBS 6" figure is the Scout Trooper w/ Speeder Bike.
Of all my TF/StarWars/Macross/Lego/Toy collection, its one of my favourite pieces.

I also highly recommend the Bespin Luke figure, which I think is the best one of the 6 Black Series Lukes.

Sand Trooper is also pretty rad. Comes with three weapons, which is just fantastic. Bit back heavy and hard to pose but.
And the classic Stormtrooper (TBS #9) is a pretty bloody awesome figure. Arguably one of the better of the whole line.

Commander Cody is a good one, and while the regular clones look good, they have some limited shoulder articulation.

I would probably give the Vader a miss - its not great. That helmet is just wrong. It seems to go for higher prices, and considering he's the centerpiece character, there are much better 6" Vader figures out there (like Mafex or SHFigs).

So long as you dont mind second hand figures, quite a few good ones pop up from time to time on ebay.
Some of the older ones (R2, Anakin, Boba, Maul) go for some pretty ridiculous prices too.
But like Facepunches said, beware the KOs (tho I have considered the $20 Darth Maul...)

TargetAU on ebay has Kylo and FO Stormtroopers for $35.

Keep your eye on the usual suspects like BBTS and HLJ for the upcoming stuff (Ashoka, Revan). Perhaps even organise splitting a case?
This wave of figures is currently available at Kmart, Myer etc for $35 if you're interested.
Rebelscum.com as a list of existing & up and coming figures which may also interest you
HLJ still have Kylo available
I'd concentrate on the newer stuff that you're keen on and gradually work back collecting the figures you're really after. BBTS also has some clearance pricing on the older Deluxe 6" figures and vehicles like these
PS: BTT for 2016 ;):p

Oh interesting, I didn't realise Takara Tomy sold Hasbro's Star Wars product in Japan. Does the TT version come out at the same time as Hasbro's? I may as well order the new figures from HLJ if they get the figures in reliably as I can just add them to my PW and ship with my Transformers.