New Mustachian here - I have experience with tax deed sales in FL (exact laws/procedures differ by state) but understand the process well and have participated in several auctions. Also, worked in entitlements/acquisitions & development for one of the big public homebuilders for years and my educational background is all real estate & construction related.
There are a lot of nuances with the tax deed sales that need to be understood prior to purchasing a property. It's not impossible, nor does it take a nonsense paid course, seminar, etc. to gain an understanding. If you're really interested, go attend an auction without any plan to purchase - no matter how good of a "deal" something might seem. There are 'pros' at the auctions and people manipulate them constantly - here in FL, I've even seen investors pay homeless people to go in and bid high to temporarily get a specific property out of the lineup - called 'burning' an auction. The property receives a winning bid but the winner never shows and the property gets rolled to next auction or one after that (dirty state I live in). Anyways...
Not sure how well versed you are already but here are some key things to learn and check on for your state... read, read, read. It's not as easy as the late night infomercials make it sound but it can be great.
Tax Deed vs. Tax Lien Certificate - know and understand the differences.
Is there an owner 'redemption' period and what is the timeframe - in FL (Broward County) - generally no. In FL, the mortgagee is wiped out which is HUGE but if you win, you could also be picking up back/prior tax liability on the property.
Tax Deed vs Warranty Deed - tax deeds generally aren't warrantable from a title company and require a 'quiet title action' to clear the title and make it marketable.
Understand land use, zoning requirements, easements, etc. - I've seen parcels/properties in S. Florida that are fully encumbered by wetland easements, utility easements or literally be a parceled 1 acre 'property' in the middle of an existing 5 acre lake.
Does the property have water use rights - big in CO and the surrounding states
Is it accessible? Not referring to physical roads but right of way access - can you get to the property or is it 'land locked' by other properties that you don't own. When land was booming, clowns were buying 1 acre parcels in no man's land west Texas that had no legal access.
Hope this helps to get you started/going.
A proud new Mustachian.