Solastranda Beach is just a 20 minute drive from Stavanger and 15 minutes from the northern end of Norwegian Scenic Route Jæren. You can even walk from the airport in about 20 minutes if you have some time to spare.
From Stavanger, follow Highway E39 south until the exit for Road 509 towards the Sola Airport. Continue following the signs towards the airport, and continue past the entrance on Nordsjøvegen. Look for the signs towards “Sola Strand Hotel”. Turn right just before your reach the beach. The parking lot is just behind the hotel.
Note that the parking lot is shared with the hotel and the hotel charges for parking in their section (unless you’re a guest). Otherwise parking is free.