Performing find on related record
I can't get my head around how to perform a find from a field from a related table.
Situation is this - I have three tables - sites, developments, organisations.
g_siteowner (autoenters siteowner)
type (siteowner / developer etc...)
On the sites layout, site::fkorganisationid is selected from TO organisation_siteownertype. This provides my filtered list to only show organisations of the type 'site owner'. The relationship is set between site::g_siteowner and organisation::type.
On the developments layout, I display the organisationsiteowner::name from a separate to from a second TO organisation_siteowner. This is related to site from site::fkorganisationid.
On the developments layout I want users to be able to perform a find based on the organisationsitewoner:name field. Ideally, I want them to select the organisation name from a value list that is filtered to only show organisations that have previously been selected as site owners. I don't want to use my existing value list I had created to display organisations of site owner type as this would also include all organisation of that type and not only those that have been selected.
My problems are two fold.
1 - How to best set up the value list to provide the correct filter list.
2 - The more pressing issue is how to perform a find on a field related from another table
Any pointers would be much appreciated.