If you’re buying from a dealer or auction house you shouldn’t have to worry about it but doesn’t sound like that’s what you’re contemplating.
If and how you go about a lien search depends to some degree on the situation and how serious you want/need to get about the search. UCC lien filings are recorded with the Secretary of State’s office in the state where the debtor resides (or resided at the time of inception of the debt). Of course that means there are a LOT of states to check just in the US and then there’s Canada as well if you want to go that far.
Since you’re in Texas, contacting the Texas Secretary of State’s office,
https://www.sos.state.tx.us/ucc/faqs.shtml, to help get you started may be a good idea. They can give you information on searching their records and UCC filings in general.
If your concerned that the debtor may have a UCC filing in another state where they previously resided and want a national or multi-state search, you may find a service less cumbersome as multiple searches in multiple states can be unreasonably time consuming. But if you’re not a lawyer or business running searches routinely, it may be a PITA setting up an account and could get pricey. Not recommending them, but
https://www.capitolservices.com/services/lien-services/ is an example.
Assuming the equipment you’re contemplating purchasing is the collateral securing a debt you should be able to search based on the identity of the equipment rather than just the individual, but I’m not familiar with the Texas SOS office and their search functions.
If there isn’t a lot of money involved and/or it’s a machine old enough to be unlikely to still be subject to lien, may not be a big deal (20 year old 20hp, etc.). If it’s new enough to have a reasonable expectation a lien likely still exists and serious money (2 year old $80k machine) and you want to be uber safe, pay a lawyer a few hundred bucks to complete due diligence on the transaction and do the paperwork on the deal. They’ll have the search service accounts and staff to do it quickly and if it turns out to be stolen or gets repossessed by an unknown lien holder, they also have the errors and omissions insurance to cover your loss caused by their mistake.
Some people deal in equipment routinely and never mess with UCC searches. Others wouldn’t buy a $3k zero turn without a thorough search. Whether you skip it completely or pay a lawyer to complete due diligence and do the paperwork or do something in between really all depends on the circumstances, how comfortable you are with the situation, and how much risk you’re willing to accept.