Unions is a meta-search engine of many UN websites and works beautifully. Unions also offers a simple directory . Here is a much simplified Unions gateway . The UN Press Release database , a part of the UN NewsCenter, stretches back to October 1995. The search is flexible with a range of field searches, including a very good category search, available from the UN Press Release search page.
Press briefing in particular are short and concise, and also searchable.
Read the current Press Briefing Highlights or search them . This is good for an overview. Start with the UNHQ website search . The United Nations publish documents in two formats. Sales Documents have a UN sales document number in addition to a UN document number.