Find the existence of a value in an Excel spreadsheet
=IF(ISERROR(VLOOKUP(<input cell>,<page>!<col>:<col>, 1, FALSE)),"No","Yes")
Returns "No" if <input cell> isn't found in column <col> on page <page>
Format Row Based on Value in a Cell
Click Conditional Formatting
Click New Rule
Choose "Use a Formula to determine which cells to format"
Enter the formula: =INDIRECT("<column>"&ROW())="<value>"
Enter the desired format (text colour, fill colour, etc).
Click OK to save the new format
