well, since the RD is coming with a 48t chain ring, i'd get a bigger cog...probably 17 or 18. if you plan on skidding a lot, i'd get a 17 so you're not constantly hitting the same spots.

as far as wheels go, i'd just look on ebay for a mavic cxp22 laced to formula track hubs. they're a safe bet, and generally regarded as a better quality wheel than the weinmann's. also, i'd get a 700c wheel just because there will be a larger variety of tires for you to choose from than if you went with a 27" wheel.

the chain is fine, but a lot of people find KMC chains are the cheapest/best/easiest to find chains around, plus KMC makes colored chains if you're into that.

hope that helps, if any of my advice is ******** i'm sure someone will let you know.