Have you looked at the Glossary or Database modules as an alternative to the forum for this activity? You could have students use the glossary adding their site name as the 'concept' then the URL and other required details as the 'definition'. If you use the database activity you can configure the fields the student completes.
Both of these activities can be configured to allow student entries, comments from others (and themselves) and grades.
The Glossary allows you to display by author and the database will allow you to sort by a specific column.
Good luck & I hope this helps!