I have created a list of OSINT tools that can be useful when doing your investigations. Though most of them have an English version, a basic knowledge of Bulgarian is required. Google and website dorking with these tools is highly beneficial and recommended. Alternatively, you can use Google translate. A word regarding the government's public data in Bulgaria - most of the registers are not electronically available, and those that are - are not fully updated. I also added non-government portals. Want me to include something? Make a pull request.
- eGov : Bulgarian eGOV open portal. Info regarding companies and people(Bulgarian & English).
- Registryagency : commercial and non/profit legal entities (Bulgarian & English).
- SearchBG : Bulgarian search engine, powered by Google (Bulgarian).
- BulMaps : Bulgarian map service (Bulgarian & English).
- BGmaps : Bulgarian map service (Bulgarian).
- BGwhois : site info; who is; trace routes; DNSBL checker; what's my ip (Bulgarian).
- Papagal : retrieves information regarding people and companies(Bulgarian).
- Register : DNS check of top-level domain .bg (Bulgarian & English).
- Vivacom : retrieves phone & address information(Bulgarian).
- Bird : political search engine but not only - Bulgarian PEPs & Communist State Security Agents (English & Bulgarian).
- Elmaz : popular dating site; browse personal information & photos (English & Bulgarian).
- VsichkiFirmi : retrieves information regarding phone number's carrier (Bulgarian).
- Yox : job portal; search by name & company (Bulgarian).
- Ukazatelite : the commercial register with advanced featues: search by keywords, address, phone, email & site (Bulgarian).
- Strazha : Parliament search engine. Search for political statements in the parliament (Bulgarian).
- Bulgarian ID number Generator : Generates possible bulgarian ID numbers from birth information.
- OLX : Popular Bulgarian online market like ebay.
- Facebook : Most used online social media website (Dorking is important).
- LinkedIn : Popular website for job seekers.
- Nekorekten : Website for checking if someone has been reported for being a scammer by using telephone number.
- Gestapo : Organisational/Business search engine for Bulgarian firms.