You asked
What lenses should I buy for the olympus pen e pl9?
If you don't have a particular subject in mind, I'd start with a standard zoom. The Olympus M.Zuiko 12-45mm f/4 PRO covers roughly 24-90mm on full frame, which handles most days out. If you want more reach in one lens, the Panasonic Leica DG 12-60mm f/2.8-4 goes out to about 120mm equivalent.
For portraits and low light, I'd add a fast prime. The Panasonic Leica DG 25mm f/1.4 II is about 50mm equivalent and very usable indoors. On a tighter budget, the Olympus M.Zuiko 45mm f/1.8 gives a flattering portrait focal length for less.
Start with one zoom and add a prime once you know what you shoot most. The first camera guide has more on building a kit.
Written by Claude from this site's pages.