Here's a little coincidence for you- I started taking Accutane yesterday too! We're Accutane buddies!
My derm recommended that I wear a moisturising sun cream rather than just a moisturiser (since your skin will get more sensitive to the sun whilst on Accutane). She recommended suncreams from Sunsense because they are not oil based so they're not greasy and they won't clog pores.
This morning I ordered SunSense Daily Face SPF50+ Invisible Tint Finish Sunscreen for everyday use and Sunsense Sun Sensitive SPF50+ Sensitive Sunscreen for when I go to hot places (or for some miracle we get a sunny day here in the UK ). I don't know where you live, but there were quite difficult to find here so I brought them from Amazon (this was also the cheapest place).
I'll let you know how I get on with these products once they arrive. I hope this helps