John Walkenbach is one of the great luminaries of the Excel/VBA world, and has been for a long time. Don't let the "for dummies" put you off - this book will be all you need until you're really pretty advanced. Although it's got an Excel slant to it, the VBA portions of this will stand you in good stead across the whole of the Office suite.

Here's the current bestselling cross-Office book. A solid seller on Amazon for a long time, Mansfield's book covers the VBA language and a lot of the features that are common to many different Office apps (the Ribbon; dialog boxes; the shared objects, et cetera). He also has some great real-world examples of VBA code in the wild.

There's actually a bit of a dearth of Word-specific VBA books around the place, which is a shame, as Word's object model is something that takes a bit of getting used to. I have to admit, I've not read this book, but it does appear to cover the important parts of automating Word (the object model; best methods to go about macro creation; distributing your macros simply).

Most VBA lives in Excel - as a VBA developer I have seen countless Excel VBA solutions which could have just been written using straightforward spreadsheet formulas. Here, then, is a thousand pages of info about Excel to help you work out exactly when you need to write a macro, and when you don't. If you're a heavy Excel and light VBA user, get this book. I am not, I promise, related to John Walkenbach. He just writes great books.

Although it's not the heaviest-used application in the Office suite, Access is almost definitely the one with the largest VBA-to-everything-else ratio. There seem to be more books about migrating from Access than anything else, but this one's a great one for those intending stretching the product to its limits.