Cissy, in case you haven't found it yet, this is the website for the park (it can sometimes be a little sticky):
http://www.parconazionale5terre.it/Eindex.php
This is the page with the trail map and some suggested itineraries:
http://www.parconazionale5terre.it/Esentieri-outdoor.php
You can zoom in on it. A trail in black means it's closed; blue lines are easy trails; green lines are a little tougher; orange lines are the most strenuous. Clicking on any of these lines will bring up the trail number and "View the itinerary" text. Clicking that text will bring up detail about the trail: difficulty; approx, time it takes to hike; terrain it passes through; etc.
And this is info on the Trekking Card you'll need to purchase if hiking either of the two 592/SVA2 "Blue Trail" segments that are usually open.
http://www.parconazionale5terre.it/Ecinque-terre-card.php
Unexpected trail closures, weather alerts or other updates pertinent to hikers will also be posted to the site. :O)