Another option would be the online Map Share Reporter (MSR) tool: [Please Register or Login to download file]
. On average, reports are accepted within a week. And once accepted, they will be implemented into a future map release usually in 6 to 12 months. According to TomTom, this online tool is the best way to submit map errors, and ensures the most direct path to the map maker guys. From my own experience, the MSR tool works quite well, and a lot of my reports have already been implemented into a TomTom map.
When there's no dedicated button for the type of error you want to report, you can always use the 'Other' category and use the comments box to explain the issue.