I don't know of a pseudocode specific forum. Pseudocode isn't really something you study; it's a half way house between an English description of the code and actual code, intended to get the flow of the code reasonably well sorted in your head without being hindered and distracted by syntax and other trivia. The format of pseudocode is fairly flexible, so the pseudocode to reverse array elements using a stack might run along the lines of:
Code:
for each entry in the array (0..end)
push it onto the stack
for each entry in the array (0..end)
pop it off the stack
There may be some more formal definitions of pseudocode out there but in general it's fairly informal. The whole point of pseudocode is to avoid all the nitty gritty stuff of a formal language; if you're going to have a detailed pseudocode language then you may as well just write the code directly, or you'll need an intermediate (pseudo-pseudocode, perhaps), to get the flow of the pseudocode sorted in your head first, but that's really missing the point.