I can log into paizo.com, but cannot log into store.paizo.com.
When I log into paizo.com and go to store.paizo.com it asks me to login
I had the same problem. It kept telling me that my email or password were wrong even though the forums recognized me just fine.
On the login page there should be a link to request an email to get in. I clicked that and then clicked to link in the email, and the store let me in.