As a French and Spanish into English translator of annual reports and contracts, my favourite resources (in no particular order) are:
• Diccionario de Términos Ecónomicos, Financieros, y Comerciales: Inglés-Español, Spanish-English by Enrique Alcaraz Varó and Brian Hughes – The only paper dictionary I still use on a regular basis.
• ECB glossary (http://bit.ly/1IW8fRF) – A comprehensive resource that clearly explains the work of the European Central Bank.
• EUR-Lex (http://bit.ly/1IUfT14) – Useful for translating contracts.
• IATE – The EU’s multilingual termbase (http://bit.ly/1TKTdIO) – Not exclusively business-related but a good source of Europe-wide terminology.
• Investopedia (http://www.investopedia.com/) – A good, comprehensive resource for learning financial terminology and keeping up-to-date with the latest developments in the business world.
• The BBC Business news website (http://www.bbc.co.uk/news/business) – Good for learning basic business terminology.
• The Economist (http://www.economist.com/) – Well written and insightful with excellent analysis of current affairs and editorials.
• Trader Finance (http://www.trader-finance.fr/) – A good monolingual French resource for checking terminology.