The Toolserver uses two mailing lists:
Toolserver users are required to read at least toolserver-announce regularly (toolserver-l includes all toolserver-announce posts). toolserver-announce is very low-traffic, so it shouldn't be a hassle. Both lists have web-accessible archives, located here: toolserver-l and toolserver-announce.
The lists provide a good way to get help if people are not available in the IRC channel (#wikimedia-toolserver) or you want broader and more thought-out comments.