I have purchased the kits they sell at Disney in the past (at the DTD World of Dis store), Mickey stickers and papers and whatnot, but found that I end up not using the stuff. I admit I'm sort of pathological about papers/supplies coordinating with the photos, and I find that between what my family is wearing and the ever-changing backgrounds, they just don't work.

(Although I have reached that point of insanity where I try to dress the fam in like-colors that "go" with the park we're visiting that day. I know, it's nuts. But it makes me happy, and no one else cares what they wear. LOL )
I do get the post-bound album with the year on it for each trip though. That's fun to have!
As much as I love seeing the red/yellow/black/white stuff, it just doesn't work for me. But Queen & Co. consistently produces amazing product lines in this color scheme. I would imagine scrapyourtrip carries them, but if you're not finding what you're looking for there scrapbook.com carries them too. Another fantastic line in that color scheme is Simple Stories "Say Cheese" -it is AMAZING!
For anyone else who approaches it like me... in general, I have found a lot of Echo Park's paper collections really coordinate well with the Magic Kingdom. I'm sure that seems like an oddball observation, but I swear it's true. LOL Lots of softer hues, without being too pastel, and even their primary colors are muted shades that just go well with the parks. Also for primary colors, Simple Stories has quite a few lines that go great with the rides and whatnot.
Pinterest is a pretty great idea resource. If you search for "name of park/ride/restaurant/character layouts" a bunch will pop up. scrapbook.com and twopeasinabucket.com also have galleries that can be searched by the theme "disney."