You might be able to find some useful info by running a whois query on the domain. The amount of information may be different depending on what the top level domain is (iirc .com domains provide more information that .nu domains, for example).
Where/how to issue the query also depends on what tld we're talking about, but .se domains, for example, I'd use LoopiaWHOIS, ie:
https://whois.loopia.se/liveforspeed.se
Excerpt:
state: active
domain: liveforspeed.se
holder: xxxtho2888-00001
admin-c: -
tech-c: -
billing-c: -
created: 2006-06-29
modified: 2015-05-12
expires: 2015-06-29
transferred: 2009-03-06
nserver: ns1.loopia.se
nserver: ns2.loopia.se
dnssec: signed delegation
status: ok
registrar: Loopia AB
In this example, the
holder information "unfortunately" has been obfuscated ("holder: xxxtho2888-00001") by the
registrar (registrar: Loopia AB).
For lfs.net (https://whois.loopia.se/lfs.net), on the other hand, we're able to find a lot more information:
Excerpt:
Registry Tech ID:
Tech Name: Victor van Vlaardingen
Tech Organization: Live for Speed
Tech Street: 16 Ladydown View
Tech City: Tisbury
Tech State/Province:
Tech Postal Code: SP3 6LL
Tech Country: GB
Tech Phone: +44.1747123456
You should be able to use LoopiaWHOIS for any tld.
Additionally, if the domain has a SSL certificate you might be able to find even more information by looking at it's details:
For example we can see that the certificate for example.com has been registered to Internet Corporation for Assigned Names and Numbers (IANA) by DigiCert:
Edit: In Sweden, companies are
required to provide their organizational number clearly on the website, which you could then use to find more information about the company (see second attachment). If a company does not provide their organizational number, or if it is at least not clear which the company is, I'd definitely consider it a dubious company and take my business elsewhere -- Obviously that might be different in other regions.