I think both sml and jeff make good points. My opinion is at this price level you get a much bigger bang for your buck with speakers than with other components--IN GENERAL. For example, you're going to hear a much bigger difference going from a $1000 pair of speakers to a $2000 pair of speakers than doing the same with an amp, preamp, or CD player within the scope of this system--again, in my opinion and in general. Yes you will hear important improvements with more expensive electronics at this level, but the relative level of improvement you'll hear for each dollar spent will be higher with speakers(as long as you don't buy absolute crap electronics--there is a limit). Therefore, at this price level my bias would be to spend more on speakers and maybe even look to a used amp, preamp, or integrated amp(but not a used CD player--too many moving parts for me to buy one of these used).
Here's the strategy I'd use. Set a budget of 2 to $3k for speakers and go listen to everything you can in that price range. Most audio enthusiasts find that some speakers just won't work for them, some they will like a lot, and then there will be one or two that just set themselves apart for you personally(remember, in addition to dealer demo discs make sure you bring your favorite music as well, and trust your own ears--they're the only ones that matter in the end). These speakers will do something for you on an emotional level that the others don't, and that should be your starting point for building your system. Also, once you have the right speakers picked out it will be easier to put the other pieces in place as those speakers will tend to work better with certain types of electronics and you'll know what your minimum power requirements will be.
Here's the bottom line: If you start with speakers you really love, even feeding them with marginal(but decent) electronics you'll likely still love the majority of what you hear. If you start with speakers you like but don't necessarily love, it is likely that no electronics(within your budget) are going to make you love them as you would if you started with the right speakers in the first place. You just can't replace the emotional tug of the right speakers, so make sure you get this part right.
Lastly, at this level I'd put cables low on the list of priorities. Yes they are absolutely important but I wouldn't spend more than $200 to $300 on them as you'll get more bang for your buck putting that money into the other components--again, at this level and in my opinion. These are good items to upgrade later if/when you feel the need.
There are lots of ways to skin this cat(I'm sure you'll hear lots of other well-founded opinions here), but this is absolutely the way I'd approach it and hope it helps. Best of luck, and don't forget to use your own ears, try stuff at home if you can, AND DON'T FORGET TO HAVE FUN.
Tim