There is now information available about walking the entirety of the Port Phillip Coast. It's conveniently packaged in my book
Coastal guide to nature and history: Port Phillip Bay. It takes a trip around the bay from Point Lonsdale to Point Nepean looking at aspects of nature (animals, plants, geology) and human history along the way. It provides guidance for access to lesser-known spots. I've walked every kilometre of the 260 km journey except where it's illegal. e.g. Point Wilson and the Point Cook RAAF Base. You can buy the book for $30 at book shops, newsagents and tourist information centres around the bay or from
http://www.coastalguidebooks.net.au. It should soon be available at the Bushwalk Australia shop. A companion volume covering Mornington Peninsula's ocean shore, Western Port, Phillip Island and French Island is due for release in November 2014.