For anyone interested in touring San Juan Island, below are some useful info/tour guide. Please note that San Juan is quite big, so it is not possible to travel to other islands in one day.
Travel Visitor Guide
You could request a copy from SanJuanIsland.org
or simply download the pdf from San Juan Island Travel Guide
In the above travel guide on page 9, it lists the map of points of interest. Each place is assigned a number.
Friday Harbor and Roche Harbor
(1 and 15 on the map)
The two ports, Roche Harbor is smaller, but might be good to take pictures.
Pelindaba Lavender Farm
(8 on the map)
You can check out the Annual Lavender Festival
. It is around July each year and free admission.
Lime Kiln Point State Park/Whale Watch Park
(9 on the map)
Best place to see whales just from the shore, but needs a bit of luck. There is a Lime Kiln Point Light-House. The scenery along the sea is beautiful.
Krystal Acres Alpaca Farm
(11 on the map)
Farm with herd of small sheep. Could be good for children to visit.
The farm is open:
10 to 5 daily from Apr through Dec.
11 to 4 daily from Jan through Mar.
Westcott Bay Sea Farms
(13 on the map)
Market with fresh oysters and seafood, sold by the pound.
Booking A Hotel
You could use Priceline.com
to compare and find a decent hotel to stay.