The south Okanagan is kind of tough to fish without a boat.
I fish all over the south Okanagan from a boat. Mostly I fish the higher lakes which unfortunately are frozen over by now. I know they fish the Okanagan, Similkameen and Ashnola rivers from the shore but I haven't done so since I was a kid. There is supposed to be some good wading spots for bass on the south end of Skaha but there again I haven't done it. If you can get over to the west Kettle river there are some good spots there but really even the west kettle is easier fished from a pontoon boat or canoe. Sadly the fly shop just closed in Penticton, its owner would know where to go to fish from shore. Yellow lake had a fly fishermans float at each end this spring but the raft on the east end broke loose during the summer It might be fixed by now, I don?t know. You can catch yellow perch from the west float if the lake isn't frozen yet.
The Okanagan river below Okanagan falls has some good spots but there again I don't fish it.
Penticton has a flyfishers club that probably would be of great help to you. I don't know their number
I cut and pasted this off the web:

Penticton Flyfishers
Meetings are held the first Thursday of every month at 7:00 P.M. except for July and August when we go fishing instead.We are a member club of the BCFFF, the BCWF and the FFF.During the winter we offer a Flytying class and a Rod building class and in the spring a Flycasting class.We also do ongoing Conservation projects with the Ministry of Environment and in our spare time, we go fishing!
Further information, please contact Bob at

I Was going to join their club but the first Thursday of the month at 7pm is my Knights of Pythias meeting and I am an officer.