It seems like you would want to search through your previously entered data to find if the information had been entered previously. For instance: if the user enters "SomeCorp" as the organization, you search through the 'organizations' column in your data until you found 'SomeCorp', then you load that address as your current address.

Internally, the data might be best storeed as a hash. Each item in your hash array would have associated keys like 'organization', 'address','phone','notes' etc. Searching through them with a forech loop is very simple.