I didn't see a thread up about the technique of adding spices to beer so I decided to make one. There are several factors to consider when adding spices to beer. Two I can think of are the surface to mass ratio (i.e. how finely ground the spices are) and extraction time (i.e. how long you let the spices stay in the beer.
For the first issue, It seems to me that breaking fresh spices down to medium chunks (e.g. cracking black peppercorns) would be the way to go. Too big might limit your ability to pull out flavor from the spice, too small and you could over extract or have a grainy texture to the beer (if unfiltered).
For the second issue, I'm interested in what others have to say. I would think that its kind of like making tea where if you leave the spices in long enough unwanted (usually bitter flavours) could be pulled out.
I guess other issues are present, like do you add spices to the fermenting beer, when do you do that, what about extracting the flavour of the spice in vodka then adding that to the beer.