Catalyst Game Labs is taking orders for their Alpha Strike companion book over on their website.
From the post:
Alpha Strike Companion adds legions of new rules and expanded options for BattleTech: Alpha Strike, the miniatures war game. With this expansion, players will unlock new tactical abilities, special warrior options, design quirks, and unit types. But more than that, players will find within these pages an expanded abstract aerospace system that will enable them to wage war from planet to jump point, while a handy conversion system opens the path to translating the stats for any BattleTech unit to its fast-playing Alpha Strike equivalent.