There are lots of good quality bookshelf speakers in your price range. What's "best" will be entirely up to your tastes, in terms of sound quality as well as looks and price. Others have mentioned several that you can look up and consider. The CM5 is one worth considering, but I think any claims that it's simply THE BEST are a bit silly.
I would agree with Bill's suggestion about getting two 12" subwoofers. One of these pairs from SVS should be nice:
Look at either the SB-1000 pair, the SB-12NSD pair, or the PB-1000 pair or PB-12NSD pair (the SB are "sealed box", the PB are "ported box" and are a little bigger physically). That would run you about $1k to $1.2k for two nice subs.
Edit: There are other good subs available too; these particular ones were the first to pop into my mind and are considered really good for the $$.
As for the fronts, also consider finding a set that has a good center speaker as well, or even consider three identical bookshelf speakers instead of the traditional 2 bookshelfs + dedicated center. The horizontal center channel speakers you typically see are built that way not for sound quality reasons but for aesthetic reasons, to fit under or above the TV set. If you can fit a 3rd bookshelf speaker there, that can work as well (and sometimes better) than a dedicated center channel.