It is not free, but the best service is likely Roddy Reports in my opinion. Also if you are serious about buying tax liens you need to attend George Jr. class on the process. His $99 class or whatever he charges now is 10x better than any of the $5000 charleton classes you can take from one of the late night gurus. You may be able to find some limited counties online now. I don't think Tarrant county lists online for free so likely you will have to pay something. You can find some information at http://www.tarrantcounty.com/econstable3/
. You can also find some info on my website under foreclosures at http://www.teamlynn.com
. George's site is on there as well. Good luck.