I've got a pair of Acoustic Energy Aesprit 301's in an office that are 5 1/2 inches wide, about 5 inches deep and 10 inches tall. They're designed to be surrounds and are not ported, which would be an advantage in your situation. I think the retail price is around $300 but I got them new here on audiogon for around $100, I think. For that small size and at the price they're quite nice.
Bookshelf speakers for HDTV
I need 2 narrow (about 6" wide) speakers to sit beside a 50" Sony SXRD. The Sony speakers do not cut it for my age impaired ears. The music considerations are minor, mostly I'm interested in dialogue clarity. Bass is also secondary. Any helpful hints, especially in the lower priced models?