Can anyone give me some info about the legitimacy of Tax Sales on homes?

[RJeAnderson4000]

I am 23 years old and i have recently sparked an interest in tax sales. Ive spent a little time researching, but most of the websites that i've found require memberships to see any info on the listings. Has anyone ever participated in a tax sale and if so can you give me some useful info to get me started!?