Well, spend time reading reviews on different Cpu's, video cards, ram, motherboards etc. and you'll start to form your own opinion based on them. Also, spend time reading reviews from different websites as well. Generally, numbers don't lie and you can find what will work for you based on games played or workload needed for parts. I have Tom's bookmarked for reviews, as well as Anandtech; and also have techPowerup listed for a good reviews from other sites directory, as well as their own.
Of course, everyone who posts suggestions on Tom's has their own parts preference/bias as well.