as mentioned earlier you need tubes with long stemmed valves due to the deep profile of the rims. they can commonly be found in 48 or 60 mm, for deep v's either will do, so just pick up what your LBS has in stock. i'd recommend against valve extenders, they work just fine, but you are running a rim that is well within the depth parameters of long stem valves - when you decide to roll on some deeeeeep carbon hoops, then you can pony up for the valve extenders.
i think you are on target in getting a 1/8 chain, and you can run a 1/8 chain with your current 3/32 chainring without problem - or - you can keep your current chain (assuming its not a 10 speed chain, as these are pretty narrow and likely less burly than, say, a 7/8 speed chain) and get a 3/32 cog. either way, you could use the crankset you already have until the new one arrives!
i roll on a number of different cranksets, and like different ones for diferent reasons, we could make a better suggestion for you if you tell us what you want/hope for in a new set of cranks - or conversly, what you dislike about your currrent set. another think you HAVE to consider is the bottom bracket interface, are you runnin' square taper, octalink,isis,.... this will likely be your first thing to consider, as it would certainly be the anti-jam if your sexy new track cranks won't fit you BB.
lastly, i might second carail's suggestion to check out sheldon's glossary, as if we know more precicely what part you are asking about we will be better able to respond, and the # of douchy responses can be pretty well cut in half. i, as well, am stumped by your questions about a splined cassette. splined is a type of interface, and cassette refers to a gear cluster. is it possible you are asking about the bottom bracket? do you have an isis BB, or perhaps you have a cartridge bearing BB which are usually found with splined cups (the bits that thread into the BB shell).
sorry for the long post, but keep at it, and we'll get 'er figgered.
Last edited by porkchop; 12-31-07 at 03:12 AM.