My husband and I will be in Bilbao for 5 days then by bus to San Sebastian for 4 days. While in San Sebastian we would like to go to Pamplona for a guided tour of the town for a day then go back to San Sebastian. Would very much appreciate knowing how I go out finding a guide with a car who can speak English.
I do know two tour guides in San Sebastian and one in Pamplona. All three are Rick Steves tour guides and all are excellent, all three speak English...and all are highly recommended. Of course, that doesn't answer your question. There very well may be an English speaking tour guide in San Sebastian with a car who is available to provide you with your wishes. I wish I could help you in that matter.
However, the "Rome2Rio" website states that the quickest form of public transportation from San Sebastian to Pamplona is by bus, with a travel time of 75 minutes and a cost as low as 6 Euros per person one way (depending on time of day and day of the week). The tour guide I recommend in Pamplona is Francisco Glaria. I will gladly provide details about contacting these three guides via Private Message, if you wish.