Armando,
Absolutely beautiful entertainment center. Where did you get it?
On the speaker advice front:
The first thing to nail down is not budget (gasp!) but rather what sort of sound you prefer. Go to some high-end audio shops in your area. Ignore the price tags. Listen to everything with some material you are familiar with (and preferably is well mastered - you'd be suprized how good speakers can reveal bad recordings!). Decide what speakers sound you like and what is pleasing to you...
You have some furniture to fit into as well. There are plenty of smart folks on this forum that can give you a paragraph or two on the pros and cons of speakers in bookshelves - but the simple run down is that aside from the speakers "fitting" the shelves around the speakers can have an effect on sound - not necessarily desirable effects.
Once you have decided on what sort of sound you like, determine your budget and look for a speaker in that range that best emulates the sound you liked. If you're stuck there are plenty of folks here and other forums that can point you toward many great speaker companies in various price classes - in my opinion, though the best bang for the buck can be had from some of the numerous internet-direct companies you'll find folks talking about here - AV123, Axiom, Ascend...
When I went through this exercise I had a lot of fun doing it, but I really dig researching and listening and getting the most out of my dollar. I found that I really enjoyed a neutral speaker - the ones that appealed the most to me were the ones that did not artificially add or remove from the original recording... I could list a lot here, but the one in a reasonable price range were the Paradigm Studio 20s V.3 at roughly $600 a pair retail. After poking around on this and other forums I found a number of other options that offered roughly the same experience for less - Ascend CBM 170 (or 340), Axiom M3 (or M22), Energy C-3... a host of others.
I tried a lot of others but ultimately did not enjoy their sound as much - B&W was too "warm" - mid-bass emphasised, Klipsch was too "bright" - high frequencies emphasized, and some did not image well at all, or ended up sounding "boxy".
After a lot of deliberation, some advice, and some in-home listening of a few models I went with the Ascends... I took a leap and got them off of Ebay even. But I've been very happy, and after a few days with them think that they provide at least the same experience as the Studio 20s that I liked... in some cases I think a little more.
Take your time, listen as much as you can. You'll find a lot of folks who claim they've found the best speaker for some dollar value but the reality is more in your head and what sound you like the most. Speakers are a personal thing, and are likely to stay the longest in your system... usually outliving multiple receivers / players / etc.
Hope this helps!
~Josh
