If you want quiet fans, then you need to get slow ones. Your main indicator of how loud the fan will be is the RPM. All manufacturers lie about their dBa figures. The only honest fan maker is Sanyo Denki. The numbers Sanyo Denki put on the San Ace fans are extremely accurate.
Anyway, to get quiet you need slow. But that means less cooling. So you will have to take that into consideration, meaning that you can't overclock to 5.0ghz, and have a quiet computer, or run SLI Titans, or something like that.
As for brands, from my personal experience, there are only two worth considering
Scythe and
Noiseblocker. Also, I would recommend a 140mm fan if you can fit it in your case. Sanyo Denki makes legendary fans. But you will need a fan controller to get them really quiet. Or you can permanently undervolt them to 7 volts, which is a pretty good solution. Here is my choice for Sanyo Denki:
http://www.newark.com/sanyo-denki-sanace-fans/9s1212l4011/fan-silent-120mm-12v-low-speed/dp/33R1003#1 choice for 140mm: Noiseblocker PK-1. This fan is nearly silent.
http://www.frozencpu.com/products/10213/fan-657/Noiseblocker_NB-BlackSilentPro_PK-1_140mm_x_25mm_Ultra_Quiet_Fan_-_700_RPM_-_9_dBA.htmlQuietest fans for 120mm were the Scythe Gentle Typhoon AP-11 (500 rpm) or the AP-12 (800 rpm), but I don't think they make them anymore. Maybe you can get used ones from ebay?
The 120mm Noiseblockers are nearly as good as the old Scythe GT's. The NB-loop model looks kooky, but they are very quiet. I have tried the PWM ones also, and the PWM Noiseblockers are the only ones that don't tick, of the ones that I've tried, which is a lot. PWM is a pretty good option, but you need PWM fan controller, or mobo headers.
As for Noctua, they are excellent quality, and have great reputation. However, they are not the quietest fans you can get. I'm not sure why their reputation is so high, given that their price is so high as well. So, in other words, Noctua's are very good, but not the best, and they are definitely overrated, and overpriced.