One form is very much like Pig Latin. From an episode of Aqua Teen Hunger Force, "I had a strizoke (stroke) in my brizain (brain) / Man I got that from Kizinkos (Kinkos)." Simple.
I think the other form just cuts off the rest of the word at a seemingly random vowel. Dizzle means Dawg/Dog/Dogg (whatever), Shizzle means sure, pizzle means piece/peace. And the latest AOL ad, "Wait just one minizzle (minute)." Context is probably the most important to knowing what the hell they're saying, in most cases.
And instead of trying to understand it, just yell out "English, motherfucker! Do you speak it?!"