It's worthwhile noting that Esri has been warning users to switch over and threatening to get rid of VBA for many years, since 10.0, and you are developing in what is essentially an unsupported environment.
ArcGIS Desktop and VBA? | ArcGIS Blog (2009)
"Is VBA supported at ArcGIS 10.1?
At ArcGIS 10.1 there will not be an ArcObjects VBA SDK nor will new VBA development with ArcGIS for Desktop be supported. There will be an optional separate setup for legacy VBA support in the ArcGIS applications. This will require an additional licence authorisation similar to ArcGIS 10.
VBA will be available if needed so existing solutions can continue to work while the code is being migrated to .NET. We recommend all users with VBA code start migrating now to an add-in or custom extension using the ArcObjects SDK for .NET or Java. This is the end of the support of VBA as a development or customisation language for ArcGIS."
- See more at: https://esriaustralia.com.au/products-arcgis-software-101-faqs#7 " (2011, emphasis mine)
To actually answer your question there's quite a bit of legacy code still available at places like stackoverflow and Geographic Information Systems Stack Exchange. I also use a lot of the original resources such as ArcObjects 10 VBA SDK Help.
Asides from the ArcObjects-specific help, there is a wealth of internet VBA resources, mostly centered around Microsoft Office, particularly Excel if you're looking for a non-GIS coding solution. So, if for example you want to get VBA to talk to Access then visiting MS support sites and forums would be the way to go.
Edit: Reworded last sentence so it didn't misconstrue Ethan's question.