And your current Yamaha system is what particularly? I'm just not much of a Klipsch fan, altho I understand their RP series is pretty good. Part of it is simply doing some research, there's plenty of articles under the AV Research tab to consider, and simply not rush out and buy everything at once. The used market is another option to save some money with, particularly for speakers. Best Buy has limited choices, particularly the one nearest me (which isn't exactly close, I prefer using the internet/shipping); do you have any other stores you can listen to other speakers at? Internet direct outfits like SVS and RSL will even allow in-home trial periods with free return on shipping, both have some well priced speakers/subs.
I'd look around the various reviews and articles about speakers here at Audioholics to start.