Taking refuge in practice My understanding of "taking refuge" is reciting a mantra.  However, is there a certain ceremony to become fully Buddhist?  Is it just repeating the mantra X number of times, or is there more to it?
Taking refuge can take many forms. You do not have to recite a mantra, although you may find it a helpful means. Taking refuge is as simple as placing your faith in the Buddha, the Dharma, or the Sangha.

For example, if you are suffering, and you remember the Four Noble Truths, and you settle your concentration on the Noble Eightfold Path -- then you have taken refuge in the Dharma.

Buddhism is a method of practice. If you follow the method, then you are already a Buddhist.