Sometimes it is useful to have to windows open at the same time, for instance the Inventory and the Contacts / Mailing List. Just go to Window->New Window
If a window opens up and is the wrong size you can scale it to fit or click its main navigation to resize it.
These are some quick key commands that come in useful.
Cmd or Ctrl
1 takes you back to the Inventory
J to show all records
F to find records
R to adjust the previous search
S for sorting found records
T omits a record from a found set
N for new record of new request
D duplicates a record (careful this is best for labels)
E deletes a record (careful, there is no undo)
cmd or ctrl =
This opens the replace field contents dialog. It will replace (overwrite) the field of all found records with the contents of the field you are in. This is useful for marking the same information across multiple records.