If you are interested get into it NOW.
Later will be too late or too expensive.
The good news, one army, the Karmans, is avaialable at Ludik Bazar (France) and Miniature Market (USA), mainly because it was the least popular choice. Karmans, aka space gorillas, still have thier following and now there is no Rackham for the apologists to suck up to we can hope for better rules balance for them. The house rules already in effect prior to Rackhams death are fairly widespread.
Robust being the best example. Which means you take one casualty/take one save from every
two wounds inflicted by as salvo of fire, round up.
If you are careful you can get into Therians or Cogs. Ludik Bazar has enough Cogs left for an army with most of the options intact, you can convert the rest. Therians are a little harder, and will require Damocles boxes plus odd boxes. Other than thart eBay, it will be impossible to get a ONI Red Blok or UNA faction now without a lucky eBay trade to start you off. Sooner or later that will die, Rackham is dead so some are chucking the hobby, others are slowly buying as they can. Both markets will dry up and we will be left with a static core of
AT-43 players most of them with large established armies.
If you are not into this game yet I would suggest taking a long look at Confrontation instead. Confrontation is to At-43 as Warhammer is to
40K. Confrontation has fifteen armies, of which only five were ever realised in the current form, but the advantage of Confrontation is the Ludik Bazar has good stock on nearly all produce.
Confrontation has an undeserved bad rep because it had a prevuious metal miniature edition which was shelved when it was repackaged and marketed alongside and identical to
AT-43, this upsert some people. However while
AT-43 is full of glaring holes, Confrontation 4th edition (which is what this is) is reaasonably well balanced abnd while rthe rulebooks are badly formatted the rules themselves are rssoanbly well thought through and make sense. Its one of the better fantasy systems out there and you can at this time buy in up to five whole armies with varying degrees of completion cheaply.
My suggestion with piccies from Google:
AT-43 human factions. Dont bother unless you see an eBay deal, only snippets of the armies are avialable. If you take a look at these models in all their glory you can see why they sell fast and you can see why those who got em keep em. Note: Though I did a Google search with '
AT-43' as the parameter, this picture which came up on page one of
images is from Dakka and is the collection of our own Lunahound.
Therians. Possible to build this up with a bit of thought from shop stock, you will need to hunt about a bit for characterts and select units.
Cogs. Yes you can make a Cog army now if you hurry, allt he characters and most of the units are there or convertible. As the core of the army you will need several Cog army boxes, as shown above.
Karmans. Highly recommended as a army choice, so long as you have an opponent. As Karmans have lots of stocka avaialbe and will likely to remain that way for some time I suggest you dont buy Karms, buy something else then come back for Karmans afterwards. they will still be there.
Confrontation.
Take a good look at this game. Five playable factions with very lose translations: Wolven (big nasty werewolves), Lion (Bretonnians), Griffin (Empire with Religion), Ram (Vampire Counts) and Scorpion (unique a genetic engineering cult, closest analogy is to Chaos). Most of the faction lists have complete stock in miniatures, excepting some heroes. Only the Lion faction has all heroes avaialbe, no faction has all the units present, but many can be converted or subbed. All the five armies are definately playable as its without need to convert stuff up.