I've just completed building out a Dolby Atmos 7.1.4 setup at my house. I would strongly recommend putting the bulk of your money on the two front speakers. They will handle music and any older movies/TV programs that are recorded in stereo only. Next up is a decent center channel, as that handles a large chunk of the sound in any multi-channel setup. For the surround speakers, it's not going to matter nearly as much. In fact, I use these $45 a pair
Dayton Audio speakers for that role.
For my main front speakers, I built them from kits. If you are handy with a table saw and router, you get a lot more bang for your buck that way. We're talking audiophile grade stuff. Granted that's not for everyone, but if that seems like something that would be fun, check these kits out:
GR Research X-Series
Parts Express Speaker Kits
With the GR Research kits, you supply the wood and have to cut, screw and glue everything together yourself. That also means you need to paint or laminate them as well. With some of the Parts Express kits, you get pre-cut or fully assembled cabinets, which makes things a lot easier.
If DIY isn't your cup of tea, then you could look into some lower end audiophile speakers as your mains. Focal has their
Chora 806 models on closeout right now for $598/pair ($400 off!). Wharfdale speakers are usually pretty good as well. If you need a cheap main speaker, the most liked model currently is the
Sony SSCS5 3-Way at $198 a pair.
Keep in mind that any bookshelf speaker is going to need a powered subwoofer though to supplement the bass.
Hope this is helpful. If you need any more recommendations, or see something you like, post it here, and I can probably help you figure out if it's decent quality. Also, it's good to buy from a place that has a good return policy, so if you hate the speaker, you can send it back hassle-free.