I have a 2 year old male American Bulldog who we just recently adopted. We have found that he will pee when his collar is touched, when startled, when he see's his leash and sometimes just for no reason at all. Does anyone have any idea how to stop this from happening?

Some dogs just pee when they're nervous... which is what that sounds like. Sadly, I don't think there is anything that can really be done :-(.

[Yogi]

your best bet is to have urine tested for possible UTI to rule out. Secondly, this can be corrected if in fact excited or nervous urinating. By avoiding the dog instead of going to a direct approach. Slowing down with the greetings etc has proven to work well with dogs who are prone to nervous and or excited peeing.
By not paying direct attention to him can in most cases alleviate this as it is brought on by a reaction generally associated to attention. By not giving him direct attention you will probably see an improvement. Over time, this behavior in most cases subsides unless it is in fact a UTI. Good luck.