As much as JcPanny's suggestion is very good, should I decide not to take his advice and wanted to broaden my search, what sub-$200 5.1 speaker system would you recommend of ANY mfg? (this is JUST for speakers, not a whole HTIB)
Thanks!
For $200 I think the best performance would be had from DIYing a set of speakers.
But, as that may not be an available option, I would suggest looking for two or three pairs (or singles, if available) of decent quality, lower price used or "last year's model" bookshelf speakers (just be sure they are not "white van" specials), and perhaps a Parts Express subwoofer. Perhaps even using some of the speakers you already have as surrounds, so that more money can be put to more important speakers (seriously, you'll appreciate an improvement in sound quality from in front of you more than you will slightly better sounding effects).
If that still breaks the bank, a Dayton
HTS-1200 (though they do have a piezo tweeter, which I'm not too sure about), and a
SUB-80 may be satisfactory
The reason I am hesitant to recommend a small, cheep sub/sat system is because they very often use small (i.e. 2.5 inch) woofers, and will then have a good sized valley in the upper bass and lower mid-range frequency response*, but that's just my thoughts, if you really like the Infinity or H/K set you mentioned earlier, you should buy what you like.
*
which can be dealt with - but not removed - by placing the sub close to the center, and putting the speakers on the wall.