Vivaldi is of course known for the ‘Four Seasons’, the first 4 works of his Op. 8 ‘The Contest Between Harmony and Invention’. His other Opus collections have a lot to offer, and are well worth checking out.
The Op. 3 ‘L’Estro Armonico’ features 12 works for 1, 2 and 4 Violins. It is well-represented with many good recordings, but a few stand out. Trevor Pinnock and the English Concert hold the top honors. The 2 CD collections of these works has been discontinued, but have been repackaged in a 5CD super bargain set from DG Archiv with numerous other concertos for about the same price as the original 2 disc set. While the Op. 3 concertos are the draw here, the other works are given excellent period-instrument performances.
Christopher Hogwood and the Ancient Academy of Music offers a bonus of 6 Flute Concertos on their original-instrument DoubleDecca bargain set. If you want a modern instrument recording, Neville Marriner and the ASMF offer great baroque style plus four other concertos on their DoubleDecca set.
The Pinnock wins on sound quality by a little and on value, but the others have a great warm atmosphere too. You really cannot go wrong with any of these sets.