Does Aldeer have a resident expert in this field ?
If so, I need some hope.

I called and looked into this last year. Basically it's an auction and you bid what interest rate you will charge. You pay delinquent taxes and if no one makes any claims you can move forward to gain ownership. If the owner comes forward they must pay you what you have in it plus interest. It's best to have an attorney to help with the process of getting the title if it comes to that.

Title can be sticky in this situation

I'm not sure if it is the same in Alabama, but we have a set percentage of 1.5%/month (and may be different by county, as far as I know), so 18% a year return over a year (or 1.5% x how ever many months they let it lapse before paying EX: if they pay after 2 months you get the full amount of taxes paid back and 3% return on those 2 months). We did it on the land behind us, but weren't successful. It is a family of 20+ members that own it and we were trying to buy a few acres for a buffer in case it is ever developed (100 ac cutover), but they flat refused. They are in a constant state of delinquency and pay on the last day of the 2 year deadline, like clockwork (they clearcut it to use for land taxes, so not sure how long their tax fund will hold out). You are only repaid the percentage plus the taxes originally owed, but there are usually a few that are won for a good but over what is owed and that overage is not repaid (basically your "juice" paid if you ultimately end up winning the right to purchase the land, otherwise if they pay it off within the timeline and you loose your extra "juice" you paid and you only get the tax burden plus interest).
About the only ones that I know that do it regularly are land lawyers that are familiar with the industry and use it more for a (one of many) revenue stream for the 18% return, in hopes of actually acquiring the land to flip later.

How do I look up tax sales in Alabama?

Each county handles there own. Ours has a website. Everything can be done on line

I tried this in Florida. Problem is groups of people have pooled their money forming corporations and they bid .25% on just about everything. They get 95% of everything in every county around me. Not worth doing for me at .25%. You can run into trouble on some of these properties as well. Really have to do your homework.