Using this fine page as a reference (http://metapundit.net/sections/blog/ajax_autocomplete_with_scriptaculous), I finally got the autocomplete function working as I wanted.
I wanted to show a venue with some extra info in brackets and when it was selected, to update a hidden input with the id of the venue from the database.
The secret to this was realising that even though I was passing the id of the link tag, it was numberical which is not allowed. So following metapundit’s advice, I added auto_ to the front of the id value. This was then stripped off with javascript and the number put into the hidden input.
Also, a nice thing about the scriptaculous autocomplete is that if you want to show extra info but not have it passed to the page, enclose it in
