you really dont have to change them unless its acting up - they have no required maint schedule.

You can see the filter in the pic here
http://www.honda-tech.com/zerothread?id=985513

You need a 14mm flare nut wrench and the new filter, along w/ new crush washers (which should come w/ the filter if you get it from honda as a kit)

All you do is remove the bolts and nuts holding the lines to the filter and replace. Takes less than 10mins
(I suggest a rag to cover it while you undo the bolts)