There are a number of ways to physically track and manage your marketing technology stack. Most companies begin with a spreadsheet, which is a good starting place and may be all that you need if you are using 30 products or fewer. If you have already begun the process of creating spreadsheets to support GDPR preparation to keep track of the Data Privacy Agreements in place with each of your data partners, you can expand this to cover additional products and attributes.
Once the number of products in the stack starts to grow, however, and the number of attributes tracked for each product increases, spreadsheets will start to become unwieldy. Some companies have gone so far as to build their own internal micro-sites to support technology tracking.