Signs of spring and gulls

What a gorgeous day here in NJ! It was in the mid to high 70's and I even saw some dude walking around town without a shirt on. As for signs of spring, our juncos have begun singing and, as I write this, I hear my first robin singing outside. Spring is here!

After work, I stopped at a park along the widest area of the Raritan River. This area of the river always has tons of gulls gathering there. Seeing as its only 10 minutes from my house, I really should bird here more. I was hoping to maybe find an Iceland Gull, Glaucous Gull, or a Lesser Black-backed Gull. As I sat there and sorted through the various plumaged Herring and Ring-billed Gulls, I wondered how people learn about gulls. The little knowledge I have of gulls is limited to what I've learned while on field trips. I purchased Jon Dunn's two videos on gulls. There is obviously a lot of care put into these videos and a lot of knowledge can be gained by studying them, but Dunn's monotone voice is enough to drive you nuts. I don't claim to be even an intermediate larophile, but I plan on continuing my learning. How have you learned about gulls? Please share.