Board Thread:Warhammer 40k General Discussion/@comment-7855563-20130411210612/@comment-3580035-20130412001148

Unfortunately, Space Wolves (I'm assuming your doing Space wolves from your username) have not yet had Horus Heresy era models released yet, or any real rules for a specific Space Wolf legion. This is because the Horus Heresy models/rules are made by Forge World, a subsidary company of Games Workshop. However, they are fully intending to make them Space Wolf specific models/rules in future, so its best if you make a 40k Space Wolf army first, and then integrate the later 30k ones when they come out (eventually, maybe in 2 years - other legions are getting priority).

As for rule compatibility, current 30k Legion rules from Forge World are fully compatible with the 40k ones, its just that their armies may not be completely balanced with 40k armies as they 30k was designed to vs other 30k armies.

As for books, the 40k rulebook is expensive but good for collectors. A mini rulebook comes in the Dark Vengeance starter set, but also comes with models for both Dark Angles and Chaos marines and whilst a better deal overall, is not worth it just for the rulebook. The Space Wolf codex is almost a must if you are going to do Space Wolves, as it contains everything you need to make the Space Wolf 40k army lists (and a lot of background stuff). For the Horus Heresy: Betrayal book, its a tad expensive if you aren't going to do pre-heresy Sons of Horus, Emperor's Children, Deathguard or World Eaters.

If you aren't doing Space Wolves, the only other specific chapters with their own 40k codex are Blood Angels, Dark Angels and Grey Knights. Every other loyalist chapter should be able to made by tailoring the list in normal Space Marine codex to suit the chapter style.

As for paints, I really have no idea.

If you are going to start a 40k army, get the relevant codex first, and then browse through both the Games Workshop website and Forge World site for models you like. Note that a legit army needs at least two troop squads (tactical marines or scouts normally), and a HQ (character). Getting the normal Space Marine codex too can allow you to build many other chapters too, so its a good buy if your interested (although it may be getting updated anear the end of this year)