I've been researching my mother's side for ten years and it is a slow process. All I can say is one has to be careful of some information found on the internet, even Ancestry.com and LDS and especially the message boards. And when looking at other family trees who seem to be related to you, I've found that some people simply copy other trees and it just creates a big mess. One link in my chain has us related to Daniel Boone which is NOT true!
Names can be difficult also. The name Elizabeth, Sarah, Sally, Betty among others repeat ad infinitum and can make my life extremely difficult.
The way I go about it is backing up my information with census records, birth certificates, death certificates, marriage certificates, etc. Those items are difficult if not impossible to come by and can be expensive, but when you find a gem like that it is very rewarding. My gg-grandfather served in the Civil War and a "cousin" of mine purchased a copy of his military records which contained a wealth of information.
Genealogy is a slow process and can get expensive. One really needs to dig deep to get the truth.
Anyway, good luck in your research.