Media playback is not supported on this device
The 25-year-old is the third Stourbridge player to join the Moors following Chris Lait and Luke Benbow.
He was team captain as they reached the third round of the FA Cup last season before losing to Wycombe.
Tonks is a long-throw specialist, and his previous clubs include Halesowen and AFC Telford United.
Find all the latest football transfers on our dedicated page.
Solihull Moors have made their seventh signing of the summer by bringing in midfielder Tom Tonks from Northern Premier League club Stourbridge.