Don't join on my account. Ancestry often has free trials for a period of time. Check it out first. Its a little expensive, especially if a person is only interested in searching for one or two families. I do considerable research for myself and others so my Ancestry, Fold3, and digital Newspapers are bundled together. Ancestry also has Texas CW veteran's pensions which is my primary focus. They also have other states.
Family Search is free, but I find it more difficult to use. It doesn't allow you to drill down to narrow your search for those hard to find ancestors. Some folks like it better than Ancestry, but they probably use it more than me and have figured out some of the tricks. There are other sites that may be free or cheaper, but I have not used them.
Mr Martin uses additional sites and can provide good advice.