If you're in Italy your italian connections should get you into one of the numerous gran fondo rides that take place ! They're meant to be even better organised than events in France.
Calendar can be found on :
http://www.bicimilano.it/
I've just pre-registered for the Maratona dles dolomites over the internet. It's just as popular as the etape (about 8,000 riders from various countries take part) with a number of classic climbs in the dolomites to be savoured, including Passo Pordoi and Passo Giau. Takes place on 2nd July, but you have to register now (today is the deadline) if you want to be in the ballot for places.
As well as this highlight on the italian cyclosportive calendar you've got the gran fondo dei nove colli in May, and the Gran Fondo di Campagnolo in June, which also attract large numbers of participants.
Re etape, the cheapest way to do it is by direct entry and book your own accommodation/travel arrangements - not necessarily the easiest way - you have to be entered in the ballot when the forms become available in Velo magazine at the end of Jan - you've got 15 days to submit your application - it says the ballot is for French residents so a French address would be helpful - The easiest way to enter is via the tour company - it's quite expensive, though I think all the places held by the tour companies disappeared ages ago in any case.