I understand that a foreigners name is spelled in katakana, but wanted to know the appropriate way of spelling a Japanese persons name. Would hiragana be preferred? Would a choice be made between a foreign name (katakana) and a native Japanese name?
Whichever is fine, but katakana tends to be preferred in formal settings. For example, when you take a message over the phone from someone who only called himself Saiki, then you can say サイキ様からお電話がありました. Saiki can be 佐伯, 斉木, 西城 and so on in kanji. Writing さいき様 is not wrong, but it may look childish.
Traditionally, katakana has been used as the default script when kanji is not available for some reason. This is why old telegraphs and old computers only supported katakana.